Observable Timing Discrepancy in pypqc
Key facts
- Attack vector
- —
- Privileges required
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- User interaction
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- Attack complexity
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- Impact type
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- Confidentiality · integrity · availability
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- Fix status
- No fix listed
No CVSS vector from any source. Fix status from GitHub.
Summary
### Impact `kyber512`, `kyber768`, and `kyber1024` on Mac OS \(or when compiled with clang\) only: An attacker able to submit many decapsulation requests against a single private key, and to gain timing information about the decapsulation, could recover the private key. Proof-of-concept exploit exists for a local attacker. CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N/E:P/RL:U/RC:C ### Patches No patch is currently available / pending upstream [PQClean#556](https://github.com/PQClean/PQClean/issues/556). ### Workarounds No workarounds have been reported. The 0.0.7 -> 0.0.7.1 upgrade, when available, should be a drop-in replacement<!--; it has no known breaking changes-->. ### References https://pqshield.com/pqshield-plugs-timing-leaks-in-kyber-ml-kem-to-improve-pqc-implementation-maturity/ https://github.com/antoonpurnal/clangover https://www.github.com/PQClean/PQClean/issues/556 https://www.github.com/pq-crystals/kyber/commit/9b8d30698a3e7449aeb34e62339d4176f11e3c6c
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | pypqc (PyPI) | 0.0.4 – 0.0.6.2 | — | No fix listed | GHSA-hvh4-5qr6-3v7r |
- pypqc (PyPI) Vendor— Affected 0.0.4 – 0.0.6.2 Fixed in — No fix listed GHSA-hvh4-5qr6-3v7r
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-03 Threatist record created from GHSA-hvh4-5qr6-3v7r
References
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences