{"id":"GHSA-cp57-fq8g-qh6v","summary":"libcrux has an Incorrect Check of Signer Response Norm During Verification","details":"The ML-DSA verification algorithm as specified in [FIPS 204, subsection 6.3](https://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.204.pdf#subsection.6.3) requires verifiers to check that the infinity norm of the deserialized signer response $z$ does not exceed $\\gamma_1 - \\beta$ (line 13 of Algorithm 8). The same check is required to be performed during signature generation.\n\nlibcrux-ml-dsa did not perform this check correctly during signature verification, accepting signatures with signer response norm above the allowed maximum value. The check is correctly performed during signing.\n\n## Impact\nApplications using libcrux-ml-dsa for signature verification would have accepted signatures that would be rejected by a conforming implementation.\n\n## Mitigation\nStarting from version `0.0.8`, signature verification uses the correct value for $\\gamma_1$ in the signer response norm check.","aliases":["RUSTSEC-2026-0077"],"modified":"2026-03-27T06:11:21.668298Z","published":"2026-03-26T18:00:28Z","database_specific":{"github_reviewed_at":"2026-03-26T18:00:28Z","nvd_published_at":null,"cwe_ids":["CWE-347"],"severity":"HIGH","github_reviewed":true},"references":[{"type":"WEB","url":"https://github.com/cryspen/libcrux/pull/1347"},{"type":"PACKAGE","url":"https://github.com/cryspen/libcrux"},{"type":"WEB","url":"https://rustsec.org/advisories/RUSTSEC-2026-0077.html"}],"affected":[{"package":{"name":"libcrux-ml-dsa","ecosystem":"crates.io","purl":"pkg:cargo/libcrux-ml-dsa"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"0.0.8"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-cp57-fq8g-qh6v/GHSA-cp57-fq8g-qh6v.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N"}]}