VULNERABILITY INTELLIGENCE

CVE-2026-6691

CVSS score7.8 HIGH
EPSS probability0.13%
CISA KEVNot currently listed
Published2026-05-06
Last modified2026-10-26
CVSS vectorCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Description

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.

Weakness classification

  • cna@mongodb.com: CWE-120
  • nvd@nist.gov: CWE-787

Primary references