A NULL pointer vulnerability was found in OpenSSL, which can be dereferenced when signatures are being verified on PKCS7 signed or signedAndEnveloped data. In case the hash algorithm used for the signature is known to the OpenSSL library but the implementation of the hash algorithm is not available, the digest initialization will fail. There is a missing check for the return value from the initialization function which later leads to invalid usage of the digest API, most likely leading to a crash.