CVE-2026-6691 Affecting mongo-c-driver package, versions *


Severity

Recommended
low

Based on Debian security rating.

Threat Intelligence

EPSS
0.13% (3rd percentile)

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  • Snyk IDSNYK-DEBIAN11-MONGOCDRIVER-16325366
  • published1 May 2026
  • disclosed6 May 2026

Introduced: 1 May 2026

CVE-2026-6691  (opens in a new tab)

How to fix?

There is no fixed version for Debian:11 mongo-c-driver.

NVD Description

Note: Versions mentioned in the description apply only to the upstream mongo-c-driver package and not the mongo-c-driver package as distributed by Debian. See How to fix? for Debian:11 relevant fixed versions and status.

The MongoDB C Driver's Cyrus SASL integration performs unsafe string copying during username canonicalization, enabling a heap buffer overflow before any authentication or network traffic. This may be triggered by passing untrusted input in the username of a MongoDB URI with authMechanism=GSSAPI.