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Vulnerability record · CVE-2026-84964 · published 3 September 2026

CVE-2026-84964: Mongodb c driver double free vulnerability

Mongodb · C Driver

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.

8.2 CVSS 4.0 High EPSS 0.26% · top 84.4% CWE-415 · Double free
8.2CVSS 4.0 base score
0.26%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
1References
22 Sep 2026Last modified by NVD

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.

CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://jira.mongodb.org/browse/CDRIVER-6409 Vendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-84964), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.