CVE-2026-6691
CVE-2026-6691CVE-2026-6691
mongodb / c_driver
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.
Scoring
| CVSS | 7.8 () |
| Vector | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
| Last modified | 2026-06-18 |