Fixes #5738: This change introduces a check for the version number of a CSR document before its signature is verified. If the version number is not 1 (encoded as zero), the verification function fails with an `X509_R_UNSUPPORTED_VERSION` error.
To minimize impact, this check is only applied when verifying a certificate signing request using the `-verify` argument, resulting in a `X509_REQ_verify` call. This ensures that malformed certificate requests are rejected by a certification authority, enhancing security and preventing potential issues.
Reviewed-by: Neil Horman <nhorman@openssl.org> Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/24677)