Software Engineering Institute

The OpenCA PKI Development Project is a Certification Authority. A vulnerability exists in the way the libCheckSignature function compares the certificate in the database and the certificate of the signer.

From the OpenCA Security Advisory:
The comparison of the certificate in the database and the certificate of the signer was only performed on base of the serial of the certificate. The design of the function can cause the acceptance
of a signature if the chain of the signature can create a trust relationship to the chain directory of OpenCA and a certificate with a matching serial exists in the used PKI.

See the OpenCA Security Advisory for further details.

OpenCA may accept the signature of a certificate if the certificate's chain is trusted by the chain directory of OpenCA. This could allow a certificate from another PKI to authorize operations on the used PKI.

Upgrade
OpenCA version 0.9.1.7 has been released to address this vulnerability.

Apply Patch
OpenCA has supplied a patch which resolves this issue.