CVE-2026-24850 json
ML-DSA Signature Verification Accepts Signatures with Repeated Hint Indices
published 2026-01-28 9 mo ago modified 2026-06-17 4 mo ago also GHSA-5x2r-hc65-25f9 , EUVD-2026-4910
- cvss
- 5.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 27%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- crates.io ml-dsa 0.1.0-rc.4
- github.com/RustCrypto/signatures@4009614 commit
- github.com/RustCrypto/signatures@b01c3b7 commit
- github.com/RustCrypto/signatures#895 pull request
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 9 mo ago
Exploit prediction
0.34% chance of exploitation in the next 30 days, higher than 27% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
| GitHub | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| crates.io | ml-dsa | >=0.0.4, <0.1.0-rc.4 |
0.1.0-rc.4 |
Affected products
- RustCrypto signatures
Classification
- Weakness
-
- CWE-347 Improper Verification of Cryptographic Signature
References
-
github.com
/RustCrypto/signatures/pull/895
web
-
github.com
/RustCrypto/signatures/commit/400961412be2e2ab787942cf30e0a9b66b37a54a
web
-
github.com
/RustCrypto/signatures/commit/b01c3b73dd08d0094e089aa234f78b6089ec1f38
web
-
github.com
/RustCrypto/signatures/security/advisories/GHSA-5x2r-hc65-25f9
web
-
github.com
/RustCrypto/signatures/issues/894
web
-
csrc.nist.gov
/pubs/fips/204/final
web
-
datatracker.ietf.org
/doc/html/rfc9881
web
-
github.com
/C2SP/wycheproof
web
-
github.com
/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_44_verify_test.json
web
-
github.com
/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_65_verify_test.json
web
-
github.com
/C2SP/wycheproof/blob/master/testvectors_v1/mldsa_87_verify_test.json
web
-
nvd.nist.gov
/vuln/detail/CVE-2026-24850
advisory
-
github.com
/RustCrypto/signatures
package
Sources
- CVE List CVE-2026-24850
- GitHub Advisory GHSA-5x2r-hc65-25f9
- NVD CVE-2026-24850
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.