CVE-2026-84964: Heap corruption via OCSP request double free from crafted multi-URL certificate in TLS client
A double free in the OpenSSL-based TLS certificate revocation checking path of the MongoDB C Driver can be reached by a TLS endpoint that the client already trusts. During the handshake, specially formed certificate data can cause the same heap object to be released twice. An unauthenticated party acting as the trusted endpoint may cause the connecting client application to terminate unexpectedly.
Affected Software
Event History
Frequently Asked Questions
What position must an attacker hold to exploit this issue?
The attacker must act as a TLS endpoint that the client already trusts. No separate authentication is required, but the endpoint must present specially formed certificate data during the TLS handshake.
Is the documented impact limited to availability?
Yes. The provided vector lists no confidentiality or integrity impact, while the documented outcome is unexpected termination of the connecting client application.