A side channel attack (Minerva). The problem is specific to the powerpc architecture. The fix was also
exclusively applied to it.
https://security-tracker.debian.org/tracker/CVE-2025-27587
https://github.com/openssl/openssl/issues/24253
https://minerva.crocs.fi.muni.cz/
There is a fix for later versions but we don't need to apply it for now.
https://github.com/openssl/openssl/commit/85cabd94958303859b1551364a609d4ff40b67a5
In addition to only being applicable to powerpc, openssl don't consider it to be covered in their
security policy, since an attacker needs additional code running on the same machine (which is not
good enough for us).