CVE-2026-24850
ML-DSA Signature Verification Accepts Signatures with Repeated Hint Indices
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
| NVDNVD · Deferred | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.34% · top 73% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.3.
Weakness
Affected products
- affected >= 0.0.4, < 0.1.0-rc.4
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- crates.ioml-dsaGHSA-5x2r-hc65-25f9 (opens in a new tab)
References (11)
- https://github.com/RustCrypto/signatures/security/advisories/GHSA-5x2r-hc65-25f9 (opens in a new tab)x_refsource_CONFIRM
- https://github.com/RustCrypto/signatures/issues/894 (opens in a new tab)x_refsource_MISC
- https://github.com/RustCrypto/signatures/pull/895 (opens in a new tab)x_refsource_MISC
- https://github.com/RustCrypto/signatures/commit/400961412be2e2ab787942cf30e0a9b66b37a54a (opens in a new tab)x_refsource_MISC
- https://github.com/RustCrypto/signatures/commit/b01c3b73dd08d0094e089aa234f78b6089ec1f38 (opens in a new tab)x_refsource_MISC
- https://csrc.nist.gov/pubs/fips/204/final (opens in a new tab)x_refsource_MISC
- https://datatracker.ietf.org/doc/html/rfc9881 (opens in a new tab)x_refsource_MISC
- https://github.com/C2SP/wycheproof (opens in a new tab)x_refsource_MISC
- https://github.com/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_44_verify_test.json (opens in a new tab)x_refsource_MISC
- https://github.com/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_65_verify_test.json (opens in a new tab)x_refsource_MISC
- https://github.com/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_87_verify_test.json (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-5x2r-hc65-25f9 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-24850)Record last updated .