CWE-208
AllowedObservable Timing Discrepancy
Abstraction: Base · Status: Incomplete
Two separate operations in a product require different amounts of time to complete, in a way that is observable to an actor and reveals security-relevant information about the state of the product, such as whether a particular operation was successful or not.
394 vulnerabilities reference this CWE, most recent first.
GHSA-6237-9HPW-GCM6
Vulnerability from github – Published: 2025-10-21 00:30 – Updated: 2025-10-21 15:30Mbed TLS before 3.6.5 allows a local timing attack against certain RSA operations, and direct calls to mbedtls_mpi_mod_inv or mbedtls_mpi_gcd.
{
"affected": [],
"aliases": [
"CVE-2025-54764"
],
"database_specific": {
"cwe_ids": [
"CWE-208"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-10-20T22:15:37Z",
"severity": "MODERATE"
},
"details": "Mbed TLS before 3.6.5 allows a local timing attack against certain RSA operations, and direct calls to mbedtls_mpi_mod_inv or mbedtls_mpi_gcd.",
"id": "GHSA-6237-9hpw-gcm6",
"modified": "2025-10-21T15:30:56Z",
"published": "2025-10-21T00:30:26Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-54764"
},
{
"type": "WEB",
"url": "https://mbed-tls.readthedocs.io/en/latest/security-advisories/mbedtls-security-advisory-2025-10-ssbleed-mstep"
},
{
"type": "WEB",
"url": "https://mbed-tls.readthedocs.io/en/latest/tech-updates/security-advisories"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-6452-5WG5-M56R
Vulnerability from github – Published: 2026-06-01 21:30 – Updated: 2026-10-02 03:31A flaw was found in gnutls. The PKCS#7 padding check, performed during decryption, was not constant-time. This timing side-channel could allow a remote attacker to potentially leak sensitive information about the padding bytes through observable timing differences. This vulnerability is a form of information disclosure.
{
"affected": [],
"aliases": [
"CVE-2026-5419"
],
"database_specific": {
"cwe_ids": [
"CWE-208"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-06-01T21:16:47Z",
"severity": "LOW"
},
"details": "A flaw was found in gnutls. The PKCS#7 padding check, performed during decryption, was not constant-time. This timing side-channel could allow a remote attacker to potentially leak sensitive information about the padding bytes through observable timing differences. This vulnerability is a form of information disclosure.",
"id": "GHSA-6452-5wg5-m56r",
"modified": "2026-10-02T03:31:03Z",
"published": "2026-06-01T21:30:45Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-5419"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2026:13274"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2026:20612"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2026:20613"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2026:26319"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2026:26409"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2026:29197"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2026:30004"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2026:32962"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2026:58981"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2026:72502"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2026:74674"
},
{
"type": "WEB",
"url": "https://access.redhat.com/security/cve/CVE-2026-5419"
},
{
"type": "WEB",
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2467686"
},
{
"type": "WEB",
"url": "https://www.gnutls.org/security-new.html#GNUTLS-SA-2026-04-29-13"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-65P9-R9H6-22VJ
Vulnerability from github – Published: 2026-03-03 20:09 – Updated: 2026-03-25 18:26Summary
AWS-LC is an open-source, general-purpose cryptographic library.
Impact
Observable timing discrepancy in AES-CCM decryption in AWS-LC allows an unauthenticated user to potentially determine authentication tag validity via timing analysis.
The impacted implementations are through the EVP CIPHER API: EVP_aes_128_ccm, EVP_aes_192_ccm, and EVP_aes_256_ccm.
Customers of AWS services do not need to take action. aws-lc-sys and aws-lc-fips-sys contain code from AWS-LC. Applications using aws-lc-sys or aws-lc-fips-sys should upgrade to the most recent releases of aws-lc-sys or aws-lc-fips-sys.
Impacted versions:
- aws-lc-sys versions: >= 0.14.0, < 0.38.0
- aws-lc-fips-sys versions: >= v0.13.0, < 0.13.12.
Patches
The patch is included in aws-lc-sys v.0.38.0 and aws-lc-fips-sys v0.13.12.
Workarounds
In the special cases of using AES-CCM with (M=4, L=2), (M=8, L=2), or (M=16, L=2), applications can workaround this issue by using AES-CCM through the EVP AEAD API using implementations EVP_aead_aes_128_ccm_bluetooth, EVP_aead_aes_128_ccm_bluetooth_8, and, EVP_aead_aes_128_ccm_matter respectively.
Otherwise, there is no workaround and applications using aws-lc-sys or aws-lc-fips-sys should upgrade to the most recent releases of aws-lc-sys or aws-lc-fips-sys.
Resources
If there are any questions or comments about this advisory, contact [AWS/Amazon] Security via thevulnerability reporting page or directly via email to aws-security@amazon.com. Please do not create a public GitHub issue.
Acknowledgement
AWS-LC would like to thank Joshua Rogers (https://joshua.hu/) for collaborating on this issue through the coordinated vulnerability disclosure process.
{
"affected": [
{
"package": {
"ecosystem": "crates.io",
"name": "aws-lc-sys"
},
"ranges": [
{
"events": [
{
"introduced": "0.14.0"
},
{
"fixed": "0.38.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "crates.io",
"name": "aws-lc-fips-sys"
},
"ranges": [
{
"events": [
{
"introduced": "0.13.0"
},
{
"fixed": "0.13.12"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [],
"database_specific": {
"cwe_ids": [
"CWE-208"
],
"github_reviewed": true,
"github_reviewed_at": "2026-03-03T20:09:25Z",
"nvd_published_at": null,
"severity": "HIGH"
},
"details": "### Summary\nAWS-LC is an open-source, general-purpose cryptographic library.\n\n### Impact\nObservable timing discrepancy in AES-CCM decryption in AWS-LC allows an unauthenticated user to potentially determine authentication tag validity via timing analysis.\n\nThe impacted implementations are through the EVP CIPHER API: EVP_aes_128_ccm, EVP_aes_192_ccm, and EVP_aes_256_ccm.\n\nCustomers of AWS services do not need to take action. aws-lc-sys and aws-lc-fips-sys contain code from AWS-LC. Applications using aws-lc-sys or aws-lc-fips-sys should upgrade to the most recent releases of aws-lc-sys or aws-lc-fips-sys.\n\n### Impacted versions: \n - aws-lc-sys versions: \u003e= 0.14.0, \u003c 0.38.0\n - aws-lc-fips-sys versions: \u003e= v0.13.0, \u003c 0.13.12.\n\n### Patches\nThe patch is included in aws-lc-sys v.0.38.0 and aws-lc-fips-sys v0.13.12.\n\n### Workarounds\nIn the special cases of using AES-CCM with (M=4, L=2), (M=8, L=2), or (M=16, L=2), applications can workaround this issue by using AES-CCM through the EVP AEAD API using implementations EVP_aead_aes_128_ccm_bluetooth, EVP_aead_aes_128_ccm_bluetooth_8, and, EVP_aead_aes_128_ccm_matter respectively.\n\nOtherwise, there is no workaround and applications using aws-lc-sys or aws-lc-fips-sys should upgrade to the most recent releases of aws-lc-sys or aws-lc-fips-sys.\n\n### Resources\nIf there are any questions or comments about this advisory, contact [AWS/Amazon] Security via the[vulnerability reporting page](https://aws.amazon.com/security/vulnerability-reporting) or directly via email to [aws-security@amazon.com](mailto:aws-security@amazon.com). Please do not create a public GitHub issue.\n\n### Acknowledgement\nAWS-LC would like to thank Joshua Rogers (https://joshua.hu/) for collaborating on this issue through the coordinated vulnerability disclosure process.",
"id": "GHSA-65p9-r9h6-22vj",
"modified": "2026-03-25T18:26:08Z",
"published": "2026-03-03T20:09:25Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/aws/aws-lc-rs/security/advisories/GHSA-65p9-r9h6-22vj"
},
{
"type": "WEB",
"url": "https://github.com/aws/aws-lc/security/advisories/GHSA-frmv-5gcm-jwxh"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-3337"
},
{
"type": "WEB",
"url": "https://aws.amazon.com/security/security-bulletins/2026-005-AWS"
},
{
"type": "PACKAGE",
"url": "https://github.com/aws/aws-lc-rs"
},
{
"type": "WEB",
"url": "https://rustsec.org/advisories/RUSTSEC-2026-0043.html"
},
{
"type": "WEB",
"url": "https://rustsec.org/advisories/RUSTSEC-2026-0045.html"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "AWS-LC has Timing Side-Channel in AES-CCM Tag Verification"
}
GHSA-66QM-G96M-4843
Vulnerability from github – Published: 2026-08-06 15:32 – Updated: 2026-08-06 15:32OMICRON StationScout before version 3.05 contains a cryptographic timing side-channel vulnerability in the backend authentication mechanism that may allow an unauthenticated attacker to forge valid authentication credentials, bypass authentication and authorization, and impersonate legitimate clients. An attacker can gain full access to the system configuration, allowing modification, reset, or unauthorized alteration of system parameters or injecting network traffic into the connected network.
{
"affected": [],
"aliases": [
"CVE-2026-16731"
],
"database_specific": {
"cwe_ids": [
"CWE-208"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-06T14:16:22Z",
"severity": "HIGH"
},
"details": "OMICRON StationScout before version 3.05 contains a cryptographic timing side-channel vulnerability in the backend authentication mechanism that may allow an unauthenticated attacker to forge valid authentication credentials, bypass authentication and authorization, and impersonate legitimate clients.\nAn attacker can gain full access to the system configuration, allowing modification, reset, or unauthorized alteration of system parameters or injecting network traffic into the connected network.",
"id": "GHSA-66qm-g96m-4843",
"modified": "2026-08-06T15:32:43Z",
"published": "2026-08-06T15:32:43Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-16731"
},
{
"type": "WEB",
"url": "https://www.omicronenergy.com/.well-known/csaf/osa-21.json"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:H/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:P/AU:X/R:X/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
]
}
GHSA-67C4-7F3G-R556
Vulnerability from github – Published: 2023-12-21 21:30 – Updated: 2023-12-21 21:30An Observable Timing Discrepancy, Covert Timing Channel vulnerability in Silabs GSDK on ARM potentially allows Padding Oracle Crypto Attack on CBC PKCS7.This issue affects GSDK: through 4.4.0.
{
"affected": [],
"aliases": [
"CVE-2023-41097"
],
"database_specific": {
"cwe_ids": [
"CWE-203",
"CWE-208"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-12-21T21:15:08Z",
"severity": "MODERATE"
},
"details": "An Observable Timing Discrepancy, Covert Timing Channel vulnerability in Silabs GSDK on ARM potentially allows Padding Oracle Crypto Attack on CBC PKCS7.This issue affects GSDK: through 4.4.0.\n\n",
"id": "GHSA-67c4-7f3g-r556",
"modified": "2023-12-21T21:30:31Z",
"published": "2023-12-21T21:30:31Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-41097"
},
{
"type": "WEB",
"url": "https://github.com/SiliconLabs/gecko_sdk/releases"
},
{
"type": "WEB",
"url": "https://siliconlabs.lightning.force.com/sfc/servlet.shepherd/document/download/069Vm0000007rArIAI?operationContext=S1"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-67V7-3G49-MXH2
Vulnerability from github – Published: 2026-02-03 21:13 – Updated: 2026-02-06 21:43Impact
A time-based user enumeration vulnerability in the user authentication functionality of PrestaShop. This vulnerability allows an attacker to determine whether a customer account exists in the system by measuring response times.
Patches
8.2.4 and 9.0.3
Workarounds
none
References
Found by Lam Yiu Tung
{
"affected": [
{
"package": {
"ecosystem": "Packagist",
"name": "prestashop/prestashop"
},
"ranges": [
{
"events": [
{
"introduced": "9.0.0-alpha.1"
},
{
"fixed": "9.0.3"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Packagist",
"name": "prestashop/prestashop"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "8.2.4"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-25597"
],
"database_specific": {
"cwe_ids": [
"CWE-208"
],
"github_reviewed": true,
"github_reviewed_at": "2026-02-03T21:13:02Z",
"nvd_published_at": "2026-02-06T21:16:17Z",
"severity": "MODERATE"
},
"details": "### Impact\nA time-based user enumeration vulnerability in the user authentication functionality of PrestaShop. This vulnerability allows an attacker to determine whether a customer account exists in the system by measuring response times.\n\n### Patches\n8.2.4 and 9.0.3\n\n### Workarounds\nnone\n\n### References\nFound by Lam Yiu Tung",
"id": "GHSA-67v7-3g49-mxh2",
"modified": "2026-02-06T21:43:34Z",
"published": "2026-02-03T21:13:02Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/PrestaShop/PrestaShop/security/advisories/GHSA-67v7-3g49-mxh2"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-25597"
},
{
"type": "PACKAGE",
"url": "https://github.com/PrestaShop/PrestaShop"
},
{
"type": "WEB",
"url": "https://github.com/PrestaShop/PrestaShop/releases/tag/8.2.4"
},
{
"type": "WEB",
"url": "https://github.com/PrestaShop/PrestaShop/releases/tag/9.0.3"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
"type": "CVSS_V3"
}
],
"summary": "PrestaShop affected by time based enumeration in FO login form"
}
GHSA-6R7G-3MM3-FHW7
Vulnerability from github – Published: 2026-03-30 21:31 – Updated: 2026-03-30 21:31A flaw in Node.js HMAC verification uses a non-constant-time comparison when validating user-provided signatures, potentially leaking timing information proportional to the number of matching bytes. Under certain threat models where high-resolution timing measurements are possible, this behavior could be exploited as a timing oracle to infer HMAC values.
Node.js already provides timing-safe comparison primitives used elsewhere in the codebase, indicating this is an oversight rather than an intentional design decision.
This vulnerability affects 20.x, 22.x, 24.x, and 25.x.
{
"affected": [],
"aliases": [
"CVE-2026-21713"
],
"database_specific": {
"cwe_ids": [
"CWE-208"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-03-30T20:16:19Z",
"severity": "MODERATE"
},
"details": "A flaw in Node.js HMAC verification uses a non-constant-time comparison when validating user-provided signatures, potentially leaking timing information proportional to the number of matching bytes. Under certain threat models where high-resolution timing measurements are possible, this behavior could be exploited as a timing oracle to infer HMAC values.\n\nNode.js already provides timing-safe comparison primitives used elsewhere in the codebase, indicating this is an oversight rather than an intentional design decision.\n\nThis vulnerability affects **20.x, 22.x, 24.x, and 25.x**.",
"id": "GHSA-6r7g-3mm3-fhw7",
"modified": "2026-03-30T21:31:04Z",
"published": "2026-03-30T21:31:04Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-21713"
},
{
"type": "WEB",
"url": "https://nodejs.org/en/blog/vulnerability/march-2026-security-releases"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-6WH4-P7Q8-98WF
Vulnerability from github – Published: 2026-07-28 09:31 – Updated: 2026-08-26 18:30In Bouncy Castle for Java from 1.73 to before 1.78, three ML-KEM (CRYSTALS-Kyber) routines divided secret-derived polynomial coefficients by the modulus q: Poly.toMsg, which decodes the decrypted message, and the ciphertext compression routines Poly.compressPoly and PolyVec.compressPolyVec. An attacker able to measure the timing of a large number of decapsulations performed with the same long-term private key can recover that key. These are the KyberSlash1 (Poly.toMsg) and KyberSlash2 (ciphertext compression) divisions. Compression performed during encapsulation operates on values that become the public ciphertext and is not affected.
{
"affected": [],
"aliases": [
"CVE-2024-14041"
],
"database_specific": {
"cwe_ids": [
"CWE-208"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-07-28T08:17:12Z",
"severity": "HIGH"
},
"details": "In Bouncy Castle for Java from 1.73 to before 1.78, three ML-KEM (CRYSTALS-Kyber) routines divided secret-derived polynomial coefficients by the modulus q: Poly.toMsg, which decodes the decrypted message, and the ciphertext compression routines Poly.compressPoly and PolyVec.compressPolyVec. An attacker able to measure the timing of a large number of decapsulations performed with the same long-term private key can recover that key. These are the KyberSlash1 (Poly.toMsg) and KyberSlash2 (ciphertext compression) divisions. Compression performed during encapsulation operates on values that become the public ciphertext and is not affected.",
"id": "GHSA-6wh4-p7q8-98wf",
"modified": "2026-08-26T18:30:34Z",
"published": "2026-07-28T09:31:28Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-14041"
},
{
"type": "WEB",
"url": "https://github.com/bcgit/bc-java/commit/1590247178f2280defa36421475f015175dfbe9e"
},
{
"type": "WEB",
"url": "https://github.com/bcgit/bc-java/commit/5adb2c5c5b462a332b01a012bea0784b40b904e5"
},
{
"type": "WEB",
"url": "https://github.com/bcgit/bc-java/wiki/CVE-2024-14041"
},
{
"type": "WEB",
"url": "https://kyberslash.cr.yp.to"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Amber",
"type": "CVSS_V4"
}
]
}
GHSA-6X2Q-H3CR-8J2H
Vulnerability from github – Published: 2026-04-24 20:36 – Updated: 2026-05-06 21:24Summary
There is a timing side-channel vulnerability in Traefik's BasicAuth middleware that allows an attacker to enumerate valid usernames through response-time differences.
The variable intended to hold a constant-time fallback secret always resolves to an empty string, causing the constant-time comparison to short-circuit in microseconds rather than performing a full bcrypt evaluation. This restores the original timing oracle and makes it possible to distinguish existing users from non-existing ones by measuring authentication response times.
Patches
- https://github.com/traefik/traefik/releases/tag/v2.11.43
- https://github.com/traefik/traefik/releases/tag/v3.6.14
- https://github.com/traefik/traefik/releases/tag/v3.7.0-rc.2
For more information
If there are any questions or comments about this advisory, please open an issue.
Original Description # BasicAuth Timing Regression: CVE-2026-32595 Fix Is a No-Op Due to Map Key/Value Confusion ## TL;DR The patch for CVE-2026-32595 is a no-op. Line 49 of `basic_auth.go` has a map key/value confusion that makes `notFoundSecret` always `""`. The "constant time" fallback calls `goauth.CheckSecret(password, "")`, which fast-fails in ~1us instead of running bcrypt (~60ms). ## Evidence (HEAD `786f7192e`, 2026-04-09) Black-box PoC against live traefik binary on port 28080: | bucket | n | median | min | |------------------------------|-----|----------|----------| | existing user (wrong pw) | 240 | 62.85 ms | 57.54 ms | | nonexistent user (wrong pw) | 400 | 0.48 ms | 0.35 ms | Median ratio: **130.4x**. Classification: **8/8 correct**. Go in-tree test: `goauth.CheckSecret` direct ratio **12,746x**. ## Root cause (4-step trace) 1. `basic_auth.go:49`: `users[slices.Collect(maps.Values(users))[0]]` -- looks up a hash as a username key, returns `""`. 2. `basic_auth.go:119-120`: calls `goauth.CheckSecret(password, "")`. 3. `go-http-auth/basic.go:87`: empty string matches no prefix, falls to default `compareMD5HashAndPassword`. 4. `basic.go:107-109`: `bytes.SplitN("", "$", 4)` returns length 1, function returns instantly. ## Files - `poc/exploit.py` -- black-box Python timing oracle - `poc/basic_auth_timing_regression_test.go` -- Go in-tree test - `poc/traefik.yml` + `poc/dynamic.yml` -- traefik config - `poc/live_http_poc_output_head.txt` -- verbatim PoC output on HEAD Koda Reef{
"affected": [
{
"package": {
"ecosystem": "Go",
"name": "github.com/traefik/traefik/v3"
},
"ranges": [
{
"events": [
{
"introduced": "3.7.0-ea.1"
},
{
"fixed": "3.7.0-rc.2"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Go",
"name": "github.com/traefik/traefik/v3"
},
"ranges": [
{
"events": [
{
"introduced": "3.0.0-beta1"
},
{
"fixed": "3.6.14"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Go",
"name": "github.com/traefik/traefik/v2"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2.11.43"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Go",
"name": "github.com/traefik/traefik"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "1.7.34"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-41263"
],
"database_specific": {
"cwe_ids": [
"CWE-208"
],
"github_reviewed": true,
"github_reviewed_at": "2026-04-24T20:36:41Z",
"nvd_published_at": "2026-04-30T21:16:33Z",
"severity": "MODERATE"
},
"details": "## Summary\n\nThere is a timing side-channel vulnerability in Traefik\u0027s BasicAuth middleware that allows an attacker to enumerate valid usernames through response-time differences.\n\nThe variable intended to hold a constant-time fallback secret always resolves to an empty string, causing the constant-time comparison to short-circuit in microseconds rather than performing a full bcrypt evaluation. This restores the original timing oracle and makes it possible to distinguish existing users from non-existing ones by measuring authentication response times.\n\n## Patches\n\n- https://github.com/traefik/traefik/releases/tag/v2.11.43\n- https://github.com/traefik/traefik/releases/tag/v3.6.14\n- https://github.com/traefik/traefik/releases/tag/v3.7.0-rc.2\n\n## For more information\n\nIf there are any questions or comments about this advisory, please [open an issue](https://github.com/traefik/traefik/issues).\n\n\u003cdetails\u003e\n\u003csummary\u003eOriginal Description\u003c/summary\u003e\n\n# BasicAuth Timing Regression: CVE-2026-32595 Fix Is a No-Op Due to Map Key/Value Confusion\n\n## TL;DR\n\nThe patch for CVE-2026-32595 is a no-op. Line 49 of `basic_auth.go` has a\nmap key/value confusion that makes `notFoundSecret` always `\"\"`. The\n\"constant time\" fallback calls `goauth.CheckSecret(password, \"\")`, which\nfast-fails in ~1us instead of running bcrypt (~60ms).\n\n## Evidence (HEAD `786f7192e`, 2026-04-09)\n\nBlack-box PoC against live traefik binary on port 28080:\n\n| bucket | n | median | min |\n|------------------------------|-----|----------|----------|\n| existing user (wrong pw) | 240 | 62.85 ms | 57.54 ms |\n| nonexistent user (wrong pw) | 400 | 0.48 ms | 0.35 ms |\n\nMedian ratio: **130.4x**. Classification: **8/8 correct**.\n\nGo in-tree test: `goauth.CheckSecret` direct ratio **12,746x**.\n\n## Root cause (4-step trace)\n\n1. `basic_auth.go:49`: `users[slices.Collect(maps.Values(users))[0]]` -- looks\n up a hash as a username key, returns `\"\"`.\n2. `basic_auth.go:119-120`: calls `goauth.CheckSecret(password, \"\")`.\n3. `go-http-auth/basic.go:87`: empty string matches no prefix, falls to default\n `compareMD5HashAndPassword`.\n4. `basic.go:107-109`: `bytes.SplitN(\"\", \"$\", 4)` returns length 1, function\n returns instantly.\n\n## Files\n\n- `poc/exploit.py` -- black-box Python timing oracle\n- `poc/basic_auth_timing_regression_test.go` -- Go in-tree test\n- `poc/traefik.yml` + `poc/dynamic.yml` -- traefik config\n- `poc/live_http_poc_output_head.txt` -- verbatim PoC output on HEAD\n\n\nKoda Reef\n\n\u003c/details\u003e\n\n---",
"id": "GHSA-6x2q-h3cr-8j2h",
"modified": "2026-05-06T21:24:51Z",
"published": "2026-04-24T20:36:41Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/traefik/traefik/security/advisories/GHSA-6x2q-h3cr-8j2h"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-41263"
},
{
"type": "PACKAGE",
"url": "https://github.com/traefik/traefik"
},
{
"type": "WEB",
"url": "https://github.com/traefik/traefik/releases/tag/v2.11.43"
},
{
"type": "WEB",
"url": "https://github.com/traefik/traefik/releases/tag/v3.6.14"
},
{
"type": "WEB",
"url": "https://github.com/traefik/traefik/releases/tag/v3.7.0-rc.2"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "Traefik: A timing side-channel vulnerability allows for valid username enumeration via BasicAuth middleware"
}
GHSA-6XWW-RMPP-RHM3
Vulnerability from github – Published: 2024-03-12 12:30 – Updated: 2024-08-05 21:31The authentication method in Apache Doris versions before 2.0.0 was vulnerable to timing attacks. Users are recommended to upgrade to version 2.0.0 + or 1.2.8, which fixes this issue.
{
"affected": [],
"aliases": [
"CVE-2023-41313"
],
"database_specific": {
"cwe_ids": [
"CWE-208"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-03-12T11:15:46Z",
"severity": "CRITICAL"
},
"details": "The authentication method in Apache Doris versions before 2.0.0 was vulnerable to timing attacks.\nUsers are recommended to upgrade to version 2.0.0 + or 1.2.8, which fixes this issue.\n\n",
"id": "GHSA-6xww-rmpp-rhm3",
"modified": "2024-08-05T21:31:18Z",
"published": "2024-03-12T12:30:48Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-41313"
},
{
"type": "WEB",
"url": "https://lists.apache.org/thread/jqczy3vxzs6q6rz9o0626j5nks9fnv95"
},
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2024/03/10/2"
}
],
"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"
}
]
}
No mitigation information available for this CWE.
CAPEC-462: Cross-Domain Search Timing
An attacker initiates cross domain HTTP / GET requests and times the server responses. The timing of these responses may leak important information on what is happening on the server. Browser's same origin policy prevents the attacker from directly reading the server responses (in the absence of any other weaknesses), but does not prevent the attacker from timing the responses to requests that the attacker issued cross domain.
CAPEC-541: Application Fingerprinting
An adversary engages in fingerprinting activities to determine the type or version of an application installed on a remote target.
CAPEC-580: System Footprinting
An adversary engages in active probing and exploration activities to determine security information about a remote target system. Often times adversaries will rely on remote applications that can be probed for system configurations.