OpenSSL 1.1.0 has an implementation bug in the PA-RISC CRYPTO_memcmp function that effectively results to only comparing the least significant bit of each byte. This allows an attacker to forge messages that would be considered as authenticated in an amount of tries lower than that guaranteed by the security claims of the scheme. The module can only be compiled by the HP-UX assembler, so that only HP-UX PA-RISC targets are affected.
Created openssl tracking bugs for this issue:
Affects: fedora-all [bug 1561263]
Created mingw-openssl tracking bugs for this issue:
Affects: epel-7 [bug 1561262]
This flaw only affects the openssl code which is compiled by the HP-UX assembler, so that only HP-UX PA-RISC arches are affected. Red Hat Enterprise Linux does not support this architecture, and therefore is not affected.