What’s Vulnerable › Vulnerabilities
CVE-2026-84964: Heap corruption via OCSP request double free from crafted multi-URL certificate in TLS client
- Severity: high (CVSS 7.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.3% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-09-03 · updated 2026-09-22
- Weakness: CWE-415
Description
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 products
- MongoDB C# Driver: from 1.17.0 before 1.30.9; from 2.0.0 before 2.5.2 — fixed in 1.30.9, 2.5.2
How to fix
Upgrade to a fixed version: MongoDB C# Driver 1.30.9, 2.5.2. Check the vendor advisory for mitigations.
References
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