{"id":"CVE-2026-24850","aliases":["GHSA-5x2r-hc65-25f9"],"url":"https://o3.security/vulnerability/CVE-2026-24850","summary":"ML-DSA Signature Verification Accepts Signatures with Repeated Hint Indices","details":"The ML-DSA crate is a Rust implementation of the Module-Lattice-Based Digital Signature Standard (ML-DSA). Starting in version 0.0.4 and prior to version 0.1.0-rc.4, the ML-DSA signature verification implementation in the RustCrypto `ml-dsa` crate incorrectly accepts signatures with repeated (duplicate) hint indices. According to the ML-DSA specification (FIPS 204 / RFC 9881), hint indices within each polynomial must be **strictly increasing**. The current implementation uses a non-strict monotonic check (`<=` instead of `<`), allowing duplicate indices. This is a regression bug. The original implementation was correct, but a commit in version 0.0.4 inadvertently changed the strict `<` comparison to `<=`, introducing the vulnerability. Version 0.1.0-rc.4 fixes the issue.","published":"2026-01-28T00:24:53.146Z","modified":"2026-08-07T11:50:31.434294791Z","cvss":{"score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"crates.io","name":"ml-dsa","fixedVersion":"0.1.0-rc.4"}],"fix":{"url":"https://github.com/RustCrypto/signatures/commit/400961412be2e2ab787942cf30e0a9b66b37a54a","label":"RustCrypto/signatures@4009614"},"references":[{"type":"WEB","url":"https://csrc.nist.gov/pubs/fips/204/final"},{"type":"WEB","url":"https://datatracker.ietf.org/doc/html/rfc9881"},{"type":"WEB","url":"https://github.com/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_44_verify_test.json"},{"type":"WEB","url":"https://github.com/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_65_verify_test.json"},{"type":"WEB","url":"https://github.com/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_87_verify_test.json"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/24xxx/CVE-2026-24850.json"},{"type":"ADVISORY","url":"https://github.com/RustCrypto/signatures/security/advisories/GHSA-5x2r-hc65-25f9"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-24850"},{"type":"REPORT","url":"https://github.com/RustCrypto/signatures/issues/894"},{"type":"FIX","url":"https://github.com/RustCrypto/signatures/commit/400961412be2e2ab787942cf30e0a9b66b37a54a"},{"type":"FIX","url":"https://github.com/RustCrypto/signatures/commit/b01c3b73dd08d0094e089aa234f78b6089ec1f38"},{"type":"FIX","url":"https://github.com/RustCrypto/signatures/pull/895"},{"type":"PACKAGE","url":"https://github.com/C2SP/wycheproof"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-07T11:50:31.434294791Z"}}