23 Oct 2026 15:48:27 UTC
Heap overflow via oversized decrypted TLS record sequence in Windows Secure Channel stream
cve-program · CVE-2026-93393 · Published
CVE-2026-93393
Heap overflow via oversized decrypted TLS record sequence in Windows Secure Channel stream
CVSS 4.0 9.2 CRITICALCVSS 3.1 8.1 HIGHCheck source for fixed versionsKEV status unknown
cve-program · CVE-2026-93393
PublishedA heap-based buffer overflow exists in the TLS transport layer of the MongoDB C Driver when built with the Windows platform TLS backend. A remote endpoint that the client connects to can cause the driver to write uncontrolled data outside the bounds of a heap allocation while processing incoming encrypted traffic after the TLS handshake completes. No authentication or user interaction is required, because the affected processing occurs before any application-level authentication completes. Triggering this issue may lead to memory corruption in the client process, disclosure of adjacent heap memory, or termination of the process.
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