Crypt::OpenSSL::X509 versions before 2.1.3 for Perl allow denial of service via NULL pointer dereference. X509V3_EXT_d2i(ext) returns NULL when an extension's DER value fails to parse. basicC, ia5string, and auth_att dereference its result without a NULL check. keyid_data also dereferences akid->keyid, which is NULL for an empty AKI SEQUENCE (DER 30 00) even when the parse succeeds. A caller invoking an affected helper on an extension from an untrusted certificate triggers a SIGSEGV that crashes the Perl process.

• https://github.com/dsully/perl-crypt-openssl-x509/commit/4c1e2370556097c253ae27abe9e1097ea377fbd2.patch
• https://metacpan.org/release/JONASBN/Crypt-OpenSSL-X509-2.1.3/source/Changes.md

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 causes a read past the allocation, exposing adjacent heap memory as the returned hash key. extensions_by_name() uses the static shortname path and is not affected.

• https://github.com/dsully/perl-crypt-openssl-x509/commit/757289bfce095455c104d4adfe9312e7b339620f.patch
• https://metacpan.org/release/JONASBN/Crypt-OpenSSL-X509-2.1.3/source/Changes.md