CVE-2026-6691
7.8 · HIGHOverview
CVE-2026-6691 is a high-severity vulnerability affecting mongodb c_driver. It was published on May 6, 2026 and has a CVSS 3.1 base score of 7.8 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.8, rated HIGH. It requires local or adjacent network access to exploit. No authentication or special privileges are required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from mongodb. Update c_driver to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| mongodb | c_driver | >= 2.1.0, < 2.1.2 | Affected |
References
Frequently Asked Questions
What is CVE-2026-6691?
CVE-2026-6691 is a high-severity vulnerability affecting mongodb c_driver. It was published on May 6, 2026 and has a CVSS 3.1 base score of 7.8 (HIGH).
How severe is CVE-2026-6691?
This vulnerability has a CVSS 3.1 base score of 7.8, rated HIGH. It requires local or adjacent network access to exploit. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-6691?
Check the references section for vendor advisories and patches from mongodb. Update c_driver to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-6691?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-6691 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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