RUSTSEC-2026-0331
Panic on Decoding Short Hybrid Keys
The deserialization functions X25519MlKem768Draft00PrivateKey::decode X25519MlKem768Draft00PublicKey::decode and XWingKemDraft06PublicKey::decode would panic during an indexing operation when provided an input slice that is shorter than the length of the given key type, i.e. shorter than 2400 bytes in the case of the X25519MlKem768Draft00 private key and shorter than 1184 bytes in the case of the X25519MlKem768Draft and XWingKemDraft06 public keys.
Impact
Applications decoding attacker provided slices into the above mentioned private and public key types could be made to panic.
Mitigation
With release of version 0.0.10 of libcrux-kem this bug has been fixed and the serialization functions return InvalidPrivateKey and InvalidPublicKey errors on invalid input buffer lengths.
We recommend users upgrade to libcrux-kem version 0.0.10.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
What each source reports
OSV Score used
8.7
Panic on Decoding Short Hybrid Keys
The deserialization functions X25519MlKem768Draft00PrivateKey::decode X25519MlKem768Draft00PublicKey::decode and XWingKemDraft06PublicKey::decode would panic during an indexing operation when provided an input slice that is shorter than the length of the given key type, i.e. shorter than 2400 bytes in the case of the X25519MlKem768Draft00 private key and shorter than 1184 bytes in the case of the X25519MlKem768Draft and XWingKemDraft06 public keys.
Impact
Applications decoding attacker provided slices into the above mentioned private and public key types could be made to panic.
Mitigation
With release of version 0.0.10 of libcrux-kem this bug has been fixed and the serialization functions return InvalidPrivateKey and InvalidPublicKey errors on invalid input buffer lengths.
We recommend users upgrade to libcrux-kem version 0.0.10.
- Record
RUSTSEC-2026-0331- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
Affected packages
| Package | Affected | Fixed |
|---|---|---|
libcrux-kemcrates.io |
0.0.0-0 up to 0.0.10 | 0.0.10 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
RUSTSEC-2026-0331 is a high vulnerability (CVSS 8.7) in libcrux-kem, published August 24, 2026. No source lists public exploit code. Fixed in libcrux-kem 0.0.10.