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.
PUBLISHED5.2CWE-120
MongoDB C Driver Cyrus SASL Canonicalization Buffer Overflow
Problem type
Affected products
MongoDB Inc.
MongoDB C Driver
<= 2.1.2 - AFFECTED
References
GitHub Security Advisories
GHSA-587q-94wg-2pfp
The MongoDB C Driver's Cyrus SASL integration performs unsafe string copying during username...
https://github.com/advisories/GHSA-587q-94wg-2pfpThe 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.
JSON source
https://cveawg.mitre.org/api/cve/CVE-2026-6691Click to expand
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