High 8.1Published Sep 17, 2026

CVE-2026-93393Heap overflow via oversized decrypted TLS record sequence in Windows Secure Channel stream

Updated under an hour ago (2026-10-19 07:00 UTC)

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It affects MongoDB Inc. C Driver. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for MongoDB Inc. C Driver

Exploited in the last 30 days

A 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.

CVSS: 8.1 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-787
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: mongodb
NVD analysis: Analyzed
Record last updated: Sep 18, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

MongoDB Inc. C Driver mongodb:c_driver (from the name)	2.4.0; from 2.3.0 through 2.3.3; from 2.2.0 through 2.2.4; from 2.1.0 through 2.1.2; from 2.0.0 through 2.0.2; from 1.30.0 through 1.30.8; from 1.29.0 through 1.29.2; from 1.28.0 through 1.28.1; and 4 more ranges	CNA record
mongodb c_driver mongodb:c_driver	from 1.10.0 before 1.30.11; from 2.2.0 before 2.5.4	NVD

References

https://jira.mongodb.org/browse/CDRIVER-6417vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.