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42 vulnerabilities by thephpleague
CVE-2026-105830 (GCVE-0-2026-105830)
Vulnerability from nvd – Published: 2026-10-08 14:10 – Updated: 2026-10-08 17:03
VLAI
EPSS
VEX
Title
league/commonmark 2.0.0 before 2.10.2 Quadratic DoS via TableStartParser
Summary
league/commonmark from 2.0.0 before 2.10.2 contains a quadratic-time denial of service vulnerability in the GitHub Flavored Markdown Table extension's TableStartParser::tryStart() block-start scan. Unauthenticated attackers can submit a large paragraph of pipe-free lines not starting with letters, forcing repeated full-buffer strpos scans that exhaust PHP worker CPU.
Severity
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-08 17:03 UTC
CWE
- CWE-400 - Uncontrolled Resource Consumption
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/league-commo… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
2.0.0 , < 2.10.2
(semver)
Unaffected: 2.10.2 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2026-09-21 00:00
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CVE-2026-105829 (GCVE-0-2026-105829)
Vulnerability from nvd – Published: 2026-10-08 14:10 – Updated: 2026-10-08 15:22
VLAI
EPSS
VEX
Title
League CommonMark 1.3.0 before 2.10.2 Stored XSS via DisallowedRawHtml Bypass
Summary
League CommonMark from 1.3.0 before 2.10.2 contains a cross-site scripting vulnerability that allows users posting Markdown to bypass the DisallowedRawHtml extension by ending raw HTML with a bare disallowed tag name. Attackers can place a lone <script or <iframe line followed by a block supplying attributes like src or onload, executing stored scripts in viewers' browsers under default GFM settings.
Severity
6.1 (Medium)
CWE
- CWE-80 - Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/league-commo… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
cpe:2.3:a:thephpleague:commonmark:-:*:*:*:*:*:*:*
|
Date Public
2026-09-21 00:00
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CVE-2026-102601 (GCVE-0-2026-102601)
Vulnerability from nvd – Published: 2026-09-29 15:26 – Updated: 2026-09-29 16:02
VLAI
EPSS
VEX
Title
Flysystem: WhitespacePathNormalizer's control-character (CorruptedPathDetected) check is bypassed by malformed UTF-8 in the path, affecting every adapter
Summary
Flysystem is an open source file storage library for PHP. Prior to 3.35.3, the default WhitespacePathNormalizer in src/WhitespacePathNormalizer.php used by Filesystem across adapters calls preg_match with the u modifier and treats both false and 0 as falsy. A path containing malformed UTF-8 causes PCRE to return false, so paths that also contain control characters bypass CorruptedPathDetected::forPath() in normalizePath(). Filesystem::write() can store such names and Filesystem::listContents() can return the raw ANSI escape sequences, allowing hidden or spoofed terminal file listings when an administrator displays them. This issue is fixed in version 3.35.3.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-29 16:01 UTC
CWE
- CWE-150 - Improper Neutralization of Escape, Meta, or Control Sequences
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/flysystem/securit… | x_refsource_CONFIRM |
| https://github.com/thephpleague/flysystem/commit/… | x_refsource_MISC |
| https://github.com/thephpleague/flysystem/release… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | flysystem |
Affected:
< 3.35.3
|
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CVE-2024-58382 (GCVE-0-2024-58382)
Vulnerability from nvd – Published: 2026-09-09 13:31 – Updated: 2026-10-08 15:21
VLAI
EPSS
VEX
Title
league/commonmark before 2.6.0 Denial of Service via Quadratic Complexity
Summary
league/commonmark versions before 2.6.0 contain polynomial time complexity vulnerabilities in Markdown parsing that allow attackers to cause denial of service. Attackers can submit carefully crafted Markdown inputs designed to trigger worst-case performance, and sending multiple requests in parallel exhausts CPU resources and PHP-FPM processes.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-09 14:53 UTC
CWE
- CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/league-commo… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
0 , < 2.6.0
(semver)
Unaffected: 2.6.0 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2024-12-07 00:00
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CVE-2026-86435 (GCVE-0-2026-86435)
Vulnerability from nvd – Published: 2026-09-07 12:53 – Updated: 2026-10-08 15:25
VLAI
EPSS
VEX
Title
commonmark 1.5.0 before 2.8.4 Denial of Service via Footnote
Summary
commonmark versions from 1.5.0 before 2.8.4 contain a denial of service vulnerability in the Footnote extension that fails to deduplicate footnote definitions. Attackers can craft documents with duplicate footnote definitions and references to create quadratic output expansion, consuming excessive memory and CPU to exhaust server resources.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-09 14:31 UTC
CWE
- CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/commonmark-1… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
1.5.0 , < 2.8.4
(semver)
Unaffected: 2.8.4 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2026-08-03 00:00
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CVE-2026-86434 (GCVE-0-2026-86434)
Vulnerability from nvd – Published: 2026-09-07 12:53 – Updated: 2026-10-08 15:25
VLAI
EPSS
VEX
Title
commonmark 2.0.0 through 2.8.3 Denial of Service via Slug Collision
Summary
league/commonmark versions >= 2.0.0 and < 2.8.4 (patched in 2.9.0) contain a denial of service vulnerability in UniqueSlugNormalizer::normalize(), which restarts its numeric-suffix search from 1 on every slug collision, resulting in O(K^2) time complexity for K headings that collapse to the same base slug. The vulnerable path is reached when HeadingPermalinkExtension, FootnoteExtension, or TableOfContentsExtension is registered. An unauthenticated attacker can force many headings onto a single base slug (e.g., via empty ATX headings, identical heading text, or punctuation-only headings) in a small Markdown document, consuming excessive CPU and denying service.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-18 17:42 UTC
CWE
- CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/commonmark-2… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
2.0.0 , < 2.8.4
(semver)
Unaffected: 2.8.4 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2026-08-03 00:00
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CVE-2026-86433 (GCVE-0-2026-86433)
Vulnerability from nvd – Published: 2026-09-07 12:53 – Updated: 2026-10-08 15:25
VLAI
EPSS
VEX
Title
commonmark 1.5.0 before 2.8.4 Denial of Service via Attributes
Summary
commonmark versions from 1.5.0 before 2.8.4 contain a denial of service vulnerability in the Attributes extension where AttributesListener::findTargetAndDirection() performs quadratic-time sibling list scanning. Unauthenticated attackers can submit approximately 32 KB of repeated attribute blocks to cause parsing to take over 5 seconds, exhausting server resources.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 12:50 UTC
CWE
- CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/commonmark-1… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
1.5.0 , < 2.8.4
(semver)
Unaffected: 2.8.4 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2026-08-03 00:00
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CVE-2026-86432 (GCVE-0-2026-86432)
Vulnerability from nvd – Published: 2026-09-07 12:53 – Updated: 2026-10-08 15:25
VLAI
EPSS
VEX
Title
commonmark 2.0.0 before 2.8.4 Denial of Service via XML
Summary
commonmark versions from 2.0.0 before 2.8.4 contain a denial of service vulnerability in XmlRenderer that emits depth-proportional indentation for every XML tag. Attackers can provide deeply nested Markdown or AST structures to cause quadratic memory consumption and output amplification, exhausting server resources.
Severity
5.3 (Medium)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-10 14:22 UTC
CWE
- CWE-405 - Asymmetric Resource Consumption (Amplification)
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/commonmark-2… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
2.0.0 , < 2.8.4
(semver)
Unaffected: 2.8.4 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2026-08-03 00:00
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CVE-2026-86431 (GCVE-0-2026-86431)
Vulnerability from nvd – Published: 2026-09-07 12:53 – Updated: 2026-10-08 15:25
VLAI
EPSS
VEX
Title
commonmark before 2.9.1 XSS via AttributesExtension form feed bypass
Summary
league/commonmark (thephpleague/commonmark) versions >= 2.7.0 and < 2.9.1 contain a cross-site scripting vulnerability in the AttributesExtension. Prefixing an attribute name with a single U+000C form feed byte (e.g. {\x0Conclick="alert(1)"}) bypasses the AttributesHelper::filterAttributes() 'on*' event-handler filter because PHP's trim() does not strip U+000C, causing the attribute to be written verbatim into the output where browsers parse it as a genuine event handler. The same prefix also defeats the allow_unsafe_links check, allowing javascript: URIs through href/src attributes even when allow_unsafe_links is false. Exploitation requires processing untrusted Markdown with the AttributesExtension enabled; the injected script executes when the rendered HTML is viewed. Fixed in 2.9.1.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 13:30 UTC
CWE
- CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://github.com/thephpleague/commonmark/commit… | patch |
| https://www.vulncheck.com/advisories/commonmark-b… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
2.7.0 , < 2.9.1
(semver)
Unaffected: 2.9.1 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2026-08-09 00:00
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CVE-2026-86430 (GCVE-0-2026-86430)
Vulnerability from nvd – Published: 2026-09-07 12:53 – Updated: 2026-10-08 15:25
VLAI
EPSS
VEX
Title
league/commonmark before 2.9.1 Denial of Service via parsing
Summary
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Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-09 14:31 UTC
CWE
- CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/league-commo… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
0.6.0 , < 2.9.1
(semver)
Unaffected: 2.9.1 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
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CVE-2026-86429 (GCVE-0-2026-86429)
Vulnerability from nvd – Published: 2026-09-07 12:53 – Updated: 2026-10-08 15:25
VLAI
EPSS
VEX
Title
commonmark before 2.9.1 Denial of Service via SmartPunct and Attributes
Summary
The league/commonmark (thephpleague/commonmark) library in versions >= 1.5.0 and < 2.9.1 contains quadratic parsing complexity in its SmartPunctExtension and AttributesExtension. When either extension is explicitly registered on the Environment (they are not enabled by default and are excluded from the standard CommonMark and GitHub-Flavored Markdown converters), an unauthenticated attacker can submit small, specially crafted Markdown documents — such as text alternating with unpaired quotes, contiguous runs of block-level attribute blocks, or repeated class attributes — to trigger disproportionate CPU consumption and cause a denial of service. Fixed in 2.9.1.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-18 17:41 UTC
CWE
- CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/commonmark-b… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
1.5.0 , < 2.9.1
(semver)
Unaffected: 2.9.1 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2026-08-09 00:00
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CVE-2026-86428 (GCVE-0-2026-86428)
Vulnerability from nvd – Published: 2026-09-07 12:53 – Updated: 2026-10-08 15:25
VLAI
EPSS
VEX
Title
commonmark 1.5.0 before 2.10.0 Denial of Service via Attributes
Summary
commonmark versions from 1.5.0 before 2.10.0 contain a denial of service vulnerability in the AttributesExtension when processing distinctly-named attributes. Attackers can submit Markdown with numerous distinct attribute names to cause quadratic-time attribute merging and filtering, consuming disproportionate CPU resources and preventing legitimate requests from completing.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 12:50 UTC
CWE
- CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/commonmark-1… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
1.5.0 , < 2.10.0
(semver)
Unaffected: 2.10.0 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2026-08-11 00:00
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CVE-2026-71488 (GCVE-0-2026-71488)
Vulnerability from nvd – Published: 2026-08-06 20:37 – Updated: 2026-08-07 17:17
VLAI
EPSS
VEX
Title
league/commonmark: Quadratic-time denial of service when parsing crafted Markdown
Summary
league/commonmark is a PHP library for parsing and rendering CommonMark Markdown. From 0.6.0 until 2.9.0, specially crafted Markdown lines can cause the parser to have quadratic time complexity when converting, because several parsing paths repeatedly rescan growing portions of a line to translate between character positions and byte positions, and the Autolink extension can also copy and validate the remaining line at every URL-like prefix, allowing an attacker who can submit Markdown for conversion to consume disproportionate CPU time with a comparatively small request. This issue is fixed in 2.9.0.
Severity
7.5 (High)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-07 17:16 UTC
CWE
Assigner
References
5 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | x_refsource_CONFIRM |
| https://github.com/thephpleague/commonmark/commit… | x_refsource_MISC |
| https://github.com/thephpleague/commonmark/commit… | x_refsource_MISC |
| https://github.com/thephpleague/commonmark/commit… | x_refsource_MISC |
| https://github.com/thephpleague/commonmark/releas… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
>= 0.6.0, < 2.9.0
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CVE-2026-71478 (GCVE-0-2026-71478)
Vulnerability from nvd – Published: 2026-08-06 20:30 – Updated: 2026-08-07 17:05
VLAI
EPSS
VEX
Title
league/commonmark: AttributesExtension href/src unsafe-link filter bypass via embedded control bytes
Summary
league/commonmark is a PHP library for parsing and rendering CommonMark Markdown. From 1.5.0 until 2.9.0, the AttributesExtension's href and src unsafe-link filter can be bypassed by embedding control bytes, such as a tab, carriage return, line feed, or leading C0 control character, in a javascript: URL that browsers discard before parsing the scheme, causing the browser to still execute the script even when the unsafe-link filter is enabled. This issue is fixed in 2.9.0.
Severity
6.1 (Medium)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-07 17:04 UTC
CWE
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | x_refsource_CONFIRM |
| https://github.com/thephpleague/commonmark/commit… | x_refsource_MISC |
| https://github.com/thephpleague/commonmark/releas… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
>= 1.5.0, <= 2.8.3
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CVE-2026-33347 (GCVE-0-2026-33347)
Vulnerability from nvd – Published: 2026-03-24 19:26 – Updated: 2026-03-26 19:52
VLAI
EPSS
VEX
Title
league/commonmark has an embed extension allowed_domains bypass
Summary
league/commonmark is a PHP Markdown parser. From version 2.3.0 to before version 2.8.2, the DomainFilteringAdapter in the Embed extension is vulnerable to an allowlist bypass due to a missing hostname boundary assertion in the domain-matching regex. An attacker-controlled domain like youtube.com.evil passes the allowlist check when youtube.com is an allowed domain. This issue has been patched in version 2.8.2.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-26 19:34 UTC
CWE
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | x_refsource_CONFIRM |
| https://github.com/thephpleague/commonmark/commit… | x_refsource_MISC |
| https://github.com/thephpleague/commonmark/releas… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
>= 2.3.0, < 2.8.2
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CVE-2026-105830 (GCVE-0-2026-105830)
Vulnerability from cvelistv5 – Published: 2026-10-08 14:10 – Updated: 2026-10-08 17:03
VLAI
EPSS
VEX
Title
league/commonmark 2.0.0 before 2.10.2 Quadratic DoS via TableStartParser
Summary
league/commonmark from 2.0.0 before 2.10.2 contains a quadratic-time denial of service vulnerability in the GitHub Flavored Markdown Table extension's TableStartParser::tryStart() block-start scan. Unauthenticated attackers can submit a large paragraph of pipe-free lines not starting with letters, forcing repeated full-buffer strpos scans that exhaust PHP worker CPU.
Severity
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-08 17:03 UTC
CWE
- CWE-400 - Uncontrolled Resource Consumption
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/league-commo… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
2.0.0 , < 2.10.2
(semver)
Unaffected: 2.10.2 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2026-09-21 00:00
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CVE-2026-105829 (GCVE-0-2026-105829)
Vulnerability from cvelistv5 – Published: 2026-10-08 14:10 – Updated: 2026-10-08 15:22
VLAI
EPSS
VEX
Title
League CommonMark 1.3.0 before 2.10.2 Stored XSS via DisallowedRawHtml Bypass
Summary
League CommonMark from 1.3.0 before 2.10.2 contains a cross-site scripting vulnerability that allows users posting Markdown to bypass the DisallowedRawHtml extension by ending raw HTML with a bare disallowed tag name. Attackers can place a lone <script or <iframe line followed by a block supplying attributes like src or onload, executing stored scripts in viewers' browsers under default GFM settings.
Severity
6.1 (Medium)
CWE
- CWE-80 - Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/league-commo… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
cpe:2.3:a:thephpleague:commonmark:-:*:*:*:*:*:*:*
|
Date Public
2026-09-21 00:00
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CVE-2026-102601 (GCVE-0-2026-102601)
Vulnerability from cvelistv5 – Published: 2026-09-29 15:26 – Updated: 2026-09-29 16:02
VLAI
EPSS
VEX
Title
Flysystem: WhitespacePathNormalizer's control-character (CorruptedPathDetected) check is bypassed by malformed UTF-8 in the path, affecting every adapter
Summary
Flysystem is an open source file storage library for PHP. Prior to 3.35.3, the default WhitespacePathNormalizer in src/WhitespacePathNormalizer.php used by Filesystem across adapters calls preg_match with the u modifier and treats both false and 0 as falsy. A path containing malformed UTF-8 causes PCRE to return false, so paths that also contain control characters bypass CorruptedPathDetected::forPath() in normalizePath(). Filesystem::write() can store such names and Filesystem::listContents() can return the raw ANSI escape sequences, allowing hidden or spoofed terminal file listings when an administrator displays them. This issue is fixed in version 3.35.3.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-29 16:01 UTC
CWE
- CWE-150 - Improper Neutralization of Escape, Meta, or Control Sequences
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/flysystem/securit… | x_refsource_CONFIRM |
| https://github.com/thephpleague/flysystem/commit/… | x_refsource_MISC |
| https://github.com/thephpleague/flysystem/release… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | flysystem |
Affected:
< 3.35.3
|
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CVE-2024-58382 (GCVE-0-2024-58382)
Vulnerability from cvelistv5 – Published: 2026-09-09 13:31 – Updated: 2026-10-08 15:21
VLAI
EPSS
VEX
Title
league/commonmark before 2.6.0 Denial of Service via Quadratic Complexity
Summary
league/commonmark versions before 2.6.0 contain polynomial time complexity vulnerabilities in Markdown parsing that allow attackers to cause denial of service. Attackers can submit carefully crafted Markdown inputs designed to trigger worst-case performance, and sending multiple requests in parallel exhausts CPU resources and PHP-FPM processes.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-09 14:53 UTC
CWE
- CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/league-commo… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
0 , < 2.6.0
(semver)
Unaffected: 2.6.0 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2024-12-07 00:00
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CVE-2026-86435 (GCVE-0-2026-86435)
Vulnerability from cvelistv5 – Published: 2026-09-07 12:53 – Updated: 2026-10-08 15:25
VLAI
EPSS
VEX
Title
commonmark 1.5.0 before 2.8.4 Denial of Service via Footnote
Summary
commonmark versions from 1.5.0 before 2.8.4 contain a denial of service vulnerability in the Footnote extension that fails to deduplicate footnote definitions. Attackers can craft documents with duplicate footnote definitions and references to create quadratic output expansion, consuming excessive memory and CPU to exhaust server resources.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-09 14:31 UTC
CWE
- CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/commonmark-1… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
1.5.0 , < 2.8.4
(semver)
Unaffected: 2.8.4 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2026-08-03 00:00
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CVE-2026-86434 (GCVE-0-2026-86434)
Vulnerability from cvelistv5 – Published: 2026-09-07 12:53 – Updated: 2026-10-08 15:25
VLAI
EPSS
VEX
Title
commonmark 2.0.0 through 2.8.3 Denial of Service via Slug Collision
Summary
league/commonmark versions >= 2.0.0 and < 2.8.4 (patched in 2.9.0) contain a denial of service vulnerability in UniqueSlugNormalizer::normalize(), which restarts its numeric-suffix search from 1 on every slug collision, resulting in O(K^2) time complexity for K headings that collapse to the same base slug. The vulnerable path is reached when HeadingPermalinkExtension, FootnoteExtension, or TableOfContentsExtension is registered. An unauthenticated attacker can force many headings onto a single base slug (e.g., via empty ATX headings, identical heading text, or punctuation-only headings) in a small Markdown document, consuming excessive CPU and denying service.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-18 17:42 UTC
CWE
- CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/commonmark-2… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
2.0.0 , < 2.8.4
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Unaffected: 2.8.4 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2026-08-03 00:00
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CVE-2026-86433 (GCVE-0-2026-86433)
Vulnerability from cvelistv5 – Published: 2026-09-07 12:53 – Updated: 2026-10-08 15:25
VLAI
EPSS
VEX
Title
commonmark 1.5.0 before 2.8.4 Denial of Service via Attributes
Summary
commonmark versions from 1.5.0 before 2.8.4 contain a denial of service vulnerability in the Attributes extension where AttributesListener::findTargetAndDirection() performs quadratic-time sibling list scanning. Unauthenticated attackers can submit approximately 32 KB of repeated attribute blocks to cause parsing to take over 5 seconds, exhausting server resources.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 12:50 UTC
CWE
- CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/commonmark-1… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
1.5.0 , < 2.8.4
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Unaffected: 2.8.4 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2026-08-03 00:00
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CVE-2026-86432 (GCVE-0-2026-86432)
Vulnerability from cvelistv5 – Published: 2026-09-07 12:53 – Updated: 2026-10-08 15:25
VLAI
EPSS
VEX
Title
commonmark 2.0.0 before 2.8.4 Denial of Service via XML
Summary
commonmark versions from 2.0.0 before 2.8.4 contain a denial of service vulnerability in XmlRenderer that emits depth-proportional indentation for every XML tag. Attackers can provide deeply nested Markdown or AST structures to cause quadratic memory consumption and output amplification, exhausting server resources.
Severity
5.3 (Medium)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-10 14:22 UTC
CWE
- CWE-405 - Asymmetric Resource Consumption (Amplification)
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/commonmark-2… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
2.0.0 , < 2.8.4
(semver)
Unaffected: 2.8.4 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2026-08-03 00:00
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CVE-2026-86431 (GCVE-0-2026-86431)
Vulnerability from cvelistv5 – Published: 2026-09-07 12:53 – Updated: 2026-10-08 15:25
VLAI
EPSS
VEX
Title
commonmark before 2.9.1 XSS via AttributesExtension form feed bypass
Summary
league/commonmark (thephpleague/commonmark) versions >= 2.7.0 and < 2.9.1 contain a cross-site scripting vulnerability in the AttributesExtension. Prefixing an attribute name with a single U+000C form feed byte (e.g. {\x0Conclick="alert(1)"}) bypasses the AttributesHelper::filterAttributes() 'on*' event-handler filter because PHP's trim() does not strip U+000C, causing the attribute to be written verbatim into the output where browsers parse it as a genuine event handler. The same prefix also defeats the allow_unsafe_links check, allowing javascript: URIs through href/src attributes even when allow_unsafe_links is false. Exploitation requires processing untrusted Markdown with the AttributesExtension enabled; the injected script executes when the rendered HTML is viewed. Fixed in 2.9.1.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 13:30 UTC
CWE
- CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://github.com/thephpleague/commonmark/commit… | patch |
| https://www.vulncheck.com/advisories/commonmark-b… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
2.7.0 , < 2.9.1
(semver)
Unaffected: 2.9.1 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2026-08-09 00:00
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CVE-2026-86430 (GCVE-0-2026-86430)
Vulnerability from cvelistv5 – Published: 2026-09-07 12:53 – Updated: 2026-10-08 15:25
VLAI
EPSS
VEX
Title
league/commonmark before 2.9.1 Denial of Service via parsing
Summary
league/commonmark versions before 2.9.1 contain multiple denial of service vulnerabilities in fenced code block detection, reference link label lookup, and emphasis delimiter processing that perform super-linear work on crafted input. Attackers can submit specially crafted Markdown with long backtick runs, nested brackets, or delimiter sequences to consume disproportionate CPU time and prevent legitimate requests from completing.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-09 14:31 UTC
CWE
- CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/league-commo… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
0.6.0 , < 2.9.1
(semver)
Unaffected: 2.9.1 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2026-08-09 00:00
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CVE-2026-86429 (GCVE-0-2026-86429)
Vulnerability from cvelistv5 – Published: 2026-09-07 12:53 – Updated: 2026-10-08 15:25
VLAI
EPSS
VEX
Title
commonmark before 2.9.1 Denial of Service via SmartPunct and Attributes
Summary
The league/commonmark (thephpleague/commonmark) library in versions >= 1.5.0 and < 2.9.1 contains quadratic parsing complexity in its SmartPunctExtension and AttributesExtension. When either extension is explicitly registered on the Environment (they are not enabled by default and are excluded from the standard CommonMark and GitHub-Flavored Markdown converters), an unauthenticated attacker can submit small, specially crafted Markdown documents — such as text alternating with unpaired quotes, contiguous runs of block-level attribute blocks, or repeated class attributes — to trigger disproportionate CPU consumption and cause a denial of service. Fixed in 2.9.1.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-18 17:41 UTC
CWE
- CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/commonmark-b… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
1.5.0 , < 2.9.1
(semver)
Unaffected: 2.9.1 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2026-08-09 00:00
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CVE-2026-86428 (GCVE-0-2026-86428)
Vulnerability from cvelistv5 – Published: 2026-09-07 12:53 – Updated: 2026-10-08 15:25
VLAI
EPSS
VEX
Title
commonmark 1.5.0 before 2.10.0 Denial of Service via Attributes
Summary
commonmark versions from 1.5.0 before 2.10.0 contain a denial of service vulnerability in the AttributesExtension when processing distinctly-named attributes. Attackers can submit Markdown with numerous distinct attribute names to cause quadratic-time attribute merging and filtering, consuming disproportionate CPU resources and preventing legitimate requests from completing.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 12:50 UTC
CWE
- CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | vendor-advisory |
| https://www.vulncheck.com/advisories/commonmark-1… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
1.5.0 , < 2.10.0
(semver)
Unaffected: 2.10.0 (semver) cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:* |
Date Public
2026-08-11 00:00
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CVE-2026-71488 (GCVE-0-2026-71488)
Vulnerability from cvelistv5 – Published: 2026-08-06 20:37 – Updated: 2026-08-07 17:17
VLAI
EPSS
VEX
Title
league/commonmark: Quadratic-time denial of service when parsing crafted Markdown
Summary
league/commonmark is a PHP library for parsing and rendering CommonMark Markdown. From 0.6.0 until 2.9.0, specially crafted Markdown lines can cause the parser to have quadratic time complexity when converting, because several parsing paths repeatedly rescan growing portions of a line to translate between character positions and byte positions, and the Autolink extension can also copy and validate the remaining line at every URL-like prefix, allowing an attacker who can submit Markdown for conversion to consume disproportionate CPU time with a comparatively small request. This issue is fixed in 2.9.0.
Severity
7.5 (High)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-07 17:16 UTC
CWE
Assigner
References
5 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | x_refsource_CONFIRM |
| https://github.com/thephpleague/commonmark/commit… | x_refsource_MISC |
| https://github.com/thephpleague/commonmark/commit… | x_refsource_MISC |
| https://github.com/thephpleague/commonmark/commit… | x_refsource_MISC |
| https://github.com/thephpleague/commonmark/releas… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
>= 0.6.0, < 2.9.0
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CVE-2026-71478 (GCVE-0-2026-71478)
Vulnerability from cvelistv5 – Published: 2026-08-06 20:30 – Updated: 2026-08-07 17:05
VLAI
EPSS
VEX
Title
league/commonmark: AttributesExtension href/src unsafe-link filter bypass via embedded control bytes
Summary
league/commonmark is a PHP library for parsing and rendering CommonMark Markdown. From 1.5.0 until 2.9.0, the AttributesExtension's href and src unsafe-link filter can be bypassed by embedding control bytes, such as a tab, carriage return, line feed, or leading C0 control character, in a javascript: URL that browsers discard before parsing the scheme, causing the browser to still execute the script even when the unsafe-link filter is enabled. This issue is fixed in 2.9.0.
Severity
6.1 (Medium)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-07 17:04 UTC
CWE
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | x_refsource_CONFIRM |
| https://github.com/thephpleague/commonmark/commit… | x_refsource_MISC |
| https://github.com/thephpleague/commonmark/releas… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
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"title": "league/commonmark: AttributesExtension href/src unsafe-link filter bypass via embedded control bytes"
}
},
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"cveId": "CVE-2026-71478",
"datePublished": "2026-08-06T20:30:32.045Z",
"dateReserved": "2026-08-06T19:56:23.724Z",
"dateUpdated": "2026-08-07T17:05:57.244Z",
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CVE-2026-33347 (GCVE-0-2026-33347)
Vulnerability from cvelistv5 – Published: 2026-03-24 19:26 – Updated: 2026-03-26 19:52
VLAI
EPSS
VEX
Title
league/commonmark has an embed extension allowed_domains bypass
Summary
league/commonmark is a PHP Markdown parser. From version 2.3.0 to before version 2.8.2, the DomainFilteringAdapter in the Embed extension is vulnerable to an allowlist bypass due to a missing hostname boundary assertion in the domain-matching regex. An attacker-controlled domain like youtube.com.evil passes the allowlist check when youtube.com is an allowed domain. This issue has been patched in version 2.8.2.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-26 19:34 UTC
CWE
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/thephpleague/commonmark/securi… | x_refsource_CONFIRM |
| https://github.com/thephpleague/commonmark/commit… | x_refsource_MISC |
| https://github.com/thephpleague/commonmark/releas… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| thephpleague | commonmark |
Affected:
>= 2.3.0, < 2.8.2
|
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