High, CVSS 8.2PyPIAmendedPublished
pypqc private key retrieval vulnerability
GHSA-rc4p-p3j9-6577
- Affected
- PyPI pypqc >= 0.0.4, < 0.0.6.1
- Fixed in
- 0.0.6.1· Vendor fix available
- Issue
- Impact kyber512, kyber768, and kyber1024 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:A/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N/E:P/RL:O/RC:C Patches Version 0.0.6.1 and newer of PyPQC is patched. Workarounds No workarounds have been reported. The 0.0.6 - 0.0.6.1 upgrade should be a drop-in replacement; it has no known breaking changes. References Timeline 1. Cryspen researchers privately reported KyberSlash to the reference implementation maintainers. 2. Peter Schwabe partially patched KyberSlash \(only "KyberSlash 1"\) in the reference implementation on December 1st, 2023, but did not document or advertise this as a security patch. https://www.github.com/pq-crystals/kyber/commit/dda29cc63af721981ee2c831cf00822e69be3220 3. Daniel J. Bernstein publicly reported KyberSlash as a security issue on…
Recommended action: Upgrade to 0.0.6.1 or later, then redeploy and verify.A vendor fix does not resolve your finding until you verify it in your own systems.