RUSTSEC-2026-0126: AVX2 Implementation Did Not Fully Reduce Intermediate Values

What to do

1. See which version you have: cargo tree -i libcrux-ml-dsa (it also shows which of your dependencies pulls it in).
2. Update within your version requirement: cargo update -p libcrux-ml-dsa. If the fix is a newer major or minor than your requirement allows, raise it in Cargo.toml (for example libcrux-ml-dsa = "0.0.9") or update the dependency that pulls it in.
3. Check again with cargo audit, or paste your Cargo.lock into our Cargo.toml checker.

Details from the advisory

The AVX2 implementation of ML-DSA did not fully reduce intermediate inputs to the inverse NTT, which leads to a testable difference in panic behaviour of internal functions compared to the portable implementation.

Impact

We are not aware of inputs to the public key generation, signing or verification APIs that trigger a panic in the AVX2 implementation because the intermediate values were not fully reduced.

Mitigation

From version 0.0.9 intermediate values on AVX2 platforms are fully reduced in alignment with the portable implementation.

References

• Package: crates.io/crates/libcrux-ml-dsa
• Advisory: rustsec.org/advisories/RUSTSEC-2026-0126.html
• Web: github.com/cryspen/libcrux/pull/1395

From the RustSec Advisory Database (CC0-1.0) via the OSV export, downloaded Oct 24, 2026. Severity score computed from the published CVSS vector.

Other advisories for libcrux-ml-dsa

• VulnerabilityRUSTSEC-2026-0076 · 2026-03-04Panic in Signature Hint Decoding During Verification
• VulnerabilityRUSTSEC-2026-0077 · 2026-03-04Incorrect Check of Signer Response Norm During Verification
• VulnerabilityRUSTSEC-2026-0125 · 2026-05-05Signature Verification on AVX2 Platforms Mishandles Edge Case

Full security history of libcrux-ml-dsa