CWE-134
AllowedUse of Externally-Controlled Format String
Abstraction: Base · Status: Draft
The product uses a function that accepts a format string as an argument, but the format string originates from an external source.
540 vulnerabilities reference this CWE, most recent first.
GHSA-GRR9-3239-9WFQ
Vulnerability from github – Published: 2024-06-19 00:31 – Updated: 2024-06-19 00:31Actiontec WCB6200Q Cookie Format String Remote Code Execution Vulnerability. This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of Actiontec WCB6200Q routers. Authentication is not required to exploit this vulnerability.
The specific flaw exists within the HTTP server. A crafted Cookie header in an HTTP request can trigger the use of a format specifier from a user-supplied string. An attacker can leverage this vulnerability to execute code in the context of the HTTP server. Was ZDI-CAN-21417.
{
"affected": [],
"aliases": [
"CVE-2024-6145"
],
"database_specific": {
"cwe_ids": [
"CWE-134"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-06-19T00:15:50Z",
"severity": "HIGH"
},
"details": "Actiontec WCB6200Q Cookie Format String Remote Code Execution Vulnerability. This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of Actiontec WCB6200Q routers. Authentication is not required to exploit this vulnerability.\n\nThe specific flaw exists within the HTTP server. A crafted Cookie header in an HTTP request can trigger the use of a format specifier from a user-supplied string. An attacker can leverage this vulnerability to execute code in the context of the HTTP server. Was ZDI-CAN-21417.",
"id": "GHSA-grr9-3239-9wfq",
"modified": "2024-06-19T00:31:58Z",
"published": "2024-06-19T00:31:58Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-6145"
},
{
"type": "WEB",
"url": "https://www.zerodayinitiative.com/advisories/ZDI-24-808"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-GRX9-955G-VJFG
Vulnerability from github – Published: 2022-08-05 00:00 – Updated: 2022-08-11 00:00Depending on the way the format strings in the card label are crafted it's possible to leak kernel stack memory. There is also the possibility for DoS due to the v4l2loopback kernel module crashing when providing the card label on request (reproduce e.g. with many %s modifiers in a row).
{
"affected": [],
"aliases": [
"CVE-2022-2652"
],
"database_specific": {
"cwe_ids": [
"CWE-134"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2022-08-04T10:15:00Z",
"severity": "MODERATE"
},
"details": "Depending on the way the format strings in the card label are crafted it\u0027s possible to leak kernel stack memory. There is also the possibility for DoS due to the v4l2loopback kernel module crashing when providing the card label on request (reproduce e.g. with many %s modifiers in a row).",
"id": "GHSA-grx9-955g-vjfg",
"modified": "2022-08-11T00:00:38Z",
"published": "2022-08-05T00:00:30Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-2652"
},
{
"type": "WEB",
"url": "https://github.com/umlaeute/v4l2loopback/commit/e4cd225557486c420f6a34411f98c575effd43dd"
},
{
"type": "WEB",
"url": "https://huntr.dev/bounties/1b055da5-7a9e-4409-99d7-030280d242d5"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-GV5C-55X7-XJXX
Vulnerability from github – Published: 2022-05-13 01:22 – Updated: 2022-05-13 01:22An issue was discovered in handler_ipcom_shell_pwd in the Interpeak IPCOMShell TELNET server on Green Hills INTEGRITY RTOS 5.0.4. When using the pwd command, the current working directory path is used as the first argument to printf() without a proper check. An attacker may thus forge a path containing format string modifiers to get a custom format string evaluated. This results in an information leak of memory addresses.
{
"affected": [],
"aliases": [
"CVE-2019-7712"
],
"database_specific": {
"cwe_ids": [
"CWE-134"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2019-03-26T01:29:00Z",
"severity": "HIGH"
},
"details": "An issue was discovered in handler_ipcom_shell_pwd in the Interpeak IPCOMShell TELNET server on Green Hills INTEGRITY RTOS 5.0.4. When using the pwd command, the current working directory path is used as the first argument to printf() without a proper check. An attacker may thus forge a path containing format string modifiers to get a custom format string evaluated. This results in an information leak of memory addresses.",
"id": "GHSA-gv5c-55x7-xjxx",
"modified": "2022-05-13T01:22:53Z",
"published": "2022-05-13T01:22:53Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-7712"
},
{
"type": "WEB",
"url": "https://github.com/bl4ckic3/GHS-Bugs"
},
{
"type": "WEB",
"url": "https://www.ghs.com/products/rtos/integrity.html"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-GXC7-QP7G-RCXJ
Vulnerability from github – Published: 2022-05-02 03:29 – Updated: 2022-05-02 03:29Multiple format string vulnerabilities in client/client.c in smbclient in Samba 3.2.0 through 3.2.12 might allow context-dependent attackers to execute arbitrary code via format string specifiers in a filename.
{
"affected": [],
"aliases": [
"CVE-2009-1886"
],
"database_specific": {
"cwe_ids": [
"CWE-134"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2009-06-25T01:30:00Z",
"severity": "HIGH"
},
"details": "Multiple format string vulnerabilities in client/client.c in smbclient in Samba 3.2.0 through 3.2.12 might allow context-dependent attackers to execute arbitrary code via format string specifiers in a filename.",
"id": "GHSA-gxc7-qp7g-rcxj",
"modified": "2022-05-02T03:29:36Z",
"published": "2022-05-02T03:29:36Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2009-1886"
},
{
"type": "WEB",
"url": "https://bugzilla.samba.org/show_bug.cgi?id=6478"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/51328"
},
{
"type": "WEB",
"url": "http://secunia.com/advisories/35539"
},
{
"type": "WEB",
"url": "http://secunia.com/advisories/35573"
},
{
"type": "WEB",
"url": "http://secunia.com/advisories/35606"
},
{
"type": "WEB",
"url": "http://secunia.com/advisories/36918"
},
{
"type": "WEB",
"url": "http://www.debian.org/security/2009/dsa-1823"
},
{
"type": "WEB",
"url": "http://www.mandriva.com/security/advisories?name=MDVSA-2009:196"
},
{
"type": "WEB",
"url": "http://www.samba.org/samba/ftp/patches/security/samba-3.2.12-CVE-2009-1886.patch"
},
{
"type": "WEB",
"url": "http://www.samba.org/samba/security/CVE-2009-1886.html"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/35472"
},
{
"type": "WEB",
"url": "http://www.securitytracker.com/id?1022441"
},
{
"type": "WEB",
"url": "http://www.slackware.com/security/viewer.php?l=slackware-security\u0026y=2009\u0026m=slackware-security.521591"
},
{
"type": "WEB",
"url": "http://www.ubuntu.com/usn/USN-839-1"
},
{
"type": "WEB",
"url": "http://www.vupen.com/english/advisories/2009/1664"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-H32H-429H-JX9Q
Vulnerability from github – Published: 2022-05-14 01:22 – Updated: 2022-05-14 01:22When using incomplete escape codes, Irssi before 1.0.6 may access data beyond the end of the string.
{
"affected": [],
"aliases": [
"CVE-2018-5205"
],
"database_specific": {
"cwe_ids": [
"CWE-134"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2018-01-06T16:29:00Z",
"severity": "HIGH"
},
"details": "When using incomplete escape codes, Irssi before 1.0.6 may access data beyond the end of the string.",
"id": "GHSA-h32h-429h-jx9q",
"modified": "2022-05-14T01:22:28Z",
"published": "2022-05-14T01:22:28Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2018-5205"
},
{
"type": "WEB",
"url": "https://irssi.org/security/irssi_sa_2018_01.txt"
},
{
"type": "WEB",
"url": "https://usn.ubuntu.com/3527-1"
},
{
"type": "WEB",
"url": "https://www.debian.org/security/2018/dsa-4162"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-H33J-RJ54-987G
Vulnerability from github – Published: 2022-05-24 16:48 – Updated: 2022-12-01 00:30The ABB IDAL HTTP server mishandles format strings in a username or cookie during the authentication process. Attempting to authenticate with the username %25s%25p%25x%25n will crash the server. Sending %08x.AAAA.%08x.%08x will log memory content from the stack.
{
"affected": [],
"aliases": [
"CVE-2019-7228"
],
"database_specific": {
"cwe_ids": [
"CWE-134"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2019-06-27T15:15:00Z",
"severity": "HIGH"
},
"details": "The ABB IDAL HTTP server mishandles format strings in a username or cookie during the authentication process. Attempting to authenticate with the username %25s%25p%25x%25n will crash the server. Sending %08x.AAAA.%08x.%08x will log memory content from the stack.",
"id": "GHSA-h33j-rj54-987g",
"modified": "2022-12-01T00:30:42Z",
"published": "2022-05-24T16:48:45Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-7228"
},
{
"type": "WEB",
"url": "https://search.abb.com/library/Download.aspx?DocumentID=3ADR010377\u0026LanguageCode=en\u0026DocumentPartId=\u0026Action=Launch"
},
{
"type": "WEB",
"url": "https://www.darkmatter.ae/xen1thlabs/abb-idal-http-server-uncontrolled-format-string-vulnerability-xl-19-012"
},
{
"type": "WEB",
"url": "http://packetstormsecurity.com/files/153404/ABB-IDAL-HTTP-Server-Uncontrolled-Format-String.html"
},
{
"type": "WEB",
"url": "http://seclists.org/fulldisclosure/2019/Jun/43"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/108886"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-H3GF-QQ8M-R4R7
Vulnerability from github – Published: 2026-06-16 06:30 – Updated: 2026-06-16 15:33Nokia SR Linux is vulnerable to local privilege escalation vulnerability due to unsanitized format validation. Successful exploitation of this vulnerability may allow an authenticated user to execute arbitrary commands with superuser privileges.
{
"affected": [],
"aliases": [
"CVE-2025-10262"
],
"database_specific": {
"cwe_ids": [
"CWE-134"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-06-16T06:16:57Z",
"severity": "MODERATE"
},
"details": "Nokia SR Linux is vulnerable to local privilege escalation vulnerability due to unsanitized format validation. Successful exploitation of this vulnerability may allow an authenticated user to execute arbitrary commands with superuser privileges.",
"id": "GHSA-h3gf-qq8m-r4r7",
"modified": "2026-06-16T15:33:47Z",
"published": "2026-06-16T06:30:24Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-10262"
},
{
"type": "WEB",
"url": "https://www.nokia.com/we-are-nokia/security/product-security-advisory/cve-2025-10262"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:L/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-H43F-RH6W-3W65
Vulnerability from github – Published: 2025-07-30 00:32 – Updated: 2025-07-30 15:35Use of Externally-Controlled Format String vulnerability in the SonicOS SSL VPN interface allows a remote unauthenticated attacker to cause service disruption.
{
"affected": [],
"aliases": [
"CVE-2025-40600"
],
"database_specific": {
"cwe_ids": [
"CWE-134"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-07-29T22:15:24Z",
"severity": "CRITICAL"
},
"details": "Use of Externally-Controlled Format String vulnerability in the SonicOS SSL VPN interface allows a remote unauthenticated attacker to cause service disruption.",
"id": "GHSA-h43f-rh6w-3w65",
"modified": "2025-07-30T15:35:51Z",
"published": "2025-07-30T00:32:18Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-40600"
},
{
"type": "WEB",
"url": "https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2025-0013"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-H49P-33VW-Q6XW
Vulnerability from github – Published: 2024-02-22 12:30 – Updated: 2024-02-22 12:30A use of externally-controlled format string in Fortinet FortiOS 7.2.0 through 7.2.4, 7.0.0 through 7.0.11, 6.4.0 through 6.4.12, 6.2.0 through 6.2.14, 6.0.0 through 6.0.16, FortiProxy 7.2.0 through 7.2.4, 7.0.0 through 7.0.10, 2.0.0 through 2.0.12, 1.2.0 through 1.2.13, 1.1.0 through 1.1.6, 1.0.0 through 1.0.7, FortiPAM 1.0.0 through 1.0.3 allows attacker to execute unauthorized code or commands via specially crafted command.
{
"affected": [],
"aliases": [
"CVE-2023-29181"
],
"database_specific": {
"cwe_ids": [
"CWE-134"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-02-22T10:15:08Z",
"severity": "HIGH"
},
"details": "A use of externally-controlled format string in Fortinet FortiOS 7.2.0 through 7.2.4, 7.0.0 through 7.0.11, 6.4.0 through 6.4.12, 6.2.0 through 6.2.14, 6.0.0 through 6.0.16, FortiProxy 7.2.0 through 7.2.4, 7.0.0 through 7.0.10, 2.0.0 through 2.0.12, 1.2.0 through 1.2.13, 1.1.0 through 1.1.6, 1.0.0 through 1.0.7, FortiPAM 1.0.0 through 1.0.3 allows attacker to execute unauthorized code or commands via specially crafted command.",
"id": "GHSA-h49p-33vw-q6xw",
"modified": "2024-02-22T12:30:55Z",
"published": "2024-02-22T12:30:55Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-29181"
},
{
"type": "WEB",
"url": "https://fortiguard.com/psirt/FG-IR-23-119"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-H4XP-827W-FFH7
Vulnerability from github – Published: 2022-05-14 01:31 – Updated: 2022-05-14 01:31H2O versions 2.0.3 and earlier and 2.1.0-beta2 and earlier allows remote attackers to cause a denial-of-service (DoS) via format string specifiers in a template file via fastcgi, mruby, proxy, redirect or reproxy.
{
"affected": [],
"aliases": [
"CVE-2016-4864"
],
"database_specific": {
"cwe_ids": [
"CWE-134"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2017-05-12T18:29:00Z",
"severity": "HIGH"
},
"details": "H2O versions 2.0.3 and earlier and 2.1.0-beta2 and earlier allows remote attackers to cause a denial-of-service (DoS) via format string specifiers in a template file via fastcgi, mruby, proxy, redirect or reproxy.",
"id": "GHSA-h4xp-827w-ffh7",
"modified": "2022-05-14T01:31:08Z",
"published": "2022-05-14T01:31:08Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2016-4864"
},
{
"type": "WEB",
"url": "https://github.com/h2o/h2o/issues/1077"
},
{
"type": "WEB",
"url": "https://jvn.jp/en/jp/JVN94779084/index.html"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
Mitigation
Choose a language that is not subject to this flaw.
Mitigation
Ensure that all format string functions are passed a static string which cannot be controlled by the user, and that the proper number of arguments are always sent to that function as well. If at all possible, use functions that do not support the %n operator in format strings. [REF-116] [REF-117]
Mitigation
Run compilers and linkers with high warning levels, since they may detect incorrect usage.
CAPEC-135: Format String Injection
An adversary includes formatting characters in a string input field on the target application. Most applications assume that users will provide static text and may respond unpredictably to the presence of formatting character. For example, in certain functions of the C programming languages such as printf, the formatting character %s will print the contents of a memory location expecting this location to identify a string and the formatting character %n prints the number of DWORD written in the memory. An adversary can use this to read or write to memory locations or files, or simply to manipulate the value of the resulting text in unexpected ways. Reading or writing memory may result in program crashes and writing memory could result in the execution of arbitrary code if the adversary can write to the program stack.
CAPEC-67: String Format Overflow in syslog()
This attack targets applications and software that uses the syslog() function insecurely. If an application does not explicitely use a format string parameter in a call to syslog(), user input can be placed in the format string parameter leading to a format string injection attack. Adversaries can then inject malicious format string commands into the function call leading to a buffer overflow. There are many reported software vulnerabilities with the root cause being a misuse of the syslog() function.