CVE-2026-88035: Heap buffer overflow via wrapped size check during SASL username canonicalization in MongoDB C Driver
Description
A size check in the client-side authentication path of the MongoDB C Driver can wrap around, so an unusually large user-name value is accepted and copied past the end of a small buffer. A party able to set the driver's connection settings may cause the application that embeds the driver to terminate unexpectedly. Reaching this code requires a build in which the optional external SASL authentication backend is present and a connection configured to use it.
Vector CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H · CWE-190
Tracked companies
Mapped from the CVE’s affected-product data, NVD CPE matches, vendor advisories or package feeds. A mapping means the vendor’s software is named, not that its hosted service was exposed.
Status incidents that name it
No tracked status incident names this CVE.
Affected vendors and products
MongoDB: C Driver
References
- CVE record on cve.org (opens in new tab)
- NVD entry (opens in new tab)
- jira.mongodb.org/browse/CDRIVER-6416 (opens in new tab)
- CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (opens in new tab)
- This product uses data from the NVD API but is not endorsed or certified by the NVD. (opens in new tab)
- Known Exploited Vulnerabilities catalog from CISA. (opens in new tab)
- EPSS scores from FIRST (Exploit Prediction Scoring System). (opens in new tab)