Observable Timing Discrepancy in pypqc
### 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