Crypt::OpenSSL::X509 versions before 2.1.3 for Perl allow a heap out-of-bounds read via a long certificate extension OID in hv_exts. When building the extension hash (via extensions(), extensions_by…

Summary

Crypt::OpenSSL::X509 versions before 2.1.3 for Perl allow a heap out-of-bounds read via a long certificate extension OID in hv_exts. When building the extension hash (via extensions(), extensions_by_long_name(), extensions_by_oid(), or has_extension_oid()), the code passes OBJ_obj2txt()'s return value as the hash-key length; because that value is the OID's full text length rather than the bytes written to the fixed-size buffer (129 bytes), an OID whose text is longer than the 129-byte buffer c…