Vulnerability Details CVE-2026-6691
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.
Exploit prediction scoring system (EPSS) score
EPSS Score 0.001
EPSS Ranking 2.7%
CVSS Severity
CVSS v3 Score 7.8
References