Quick answers
- Is CVE-2026-88035 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-88035 being exploited in the wild.
- How severe is CVE-2026-88035?
- Medium severity, with a CVSS score of 4.7, published 10 September 2026.
- Which products and versions are affected?
- MongoDB C Driver before 1.30.10 and 2.5.3.
- Is there a fix for CVE-2026-88035?
- A patch was published on 2026-09-10. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-88035 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-88035?
- Check whether you run MongoDB C Driver at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The vulnerability is an integer overflow in the size check of the client-side authentication path when using the optional external SASL authentication backend. When a username exceeds a certain length threshold, the size check wraps around due to integer overflow, causing an undersized buffer to accept an oversized username value. This leads to a buffer overflow that writes past the allocated buffer boundary. The vulnerability requires the external SASL authentication backend to be compiled in and a connection explicitly configured to use it. An attacker who can control the driver's connection settings (username, authentication mechanism) can trigger the flaw and cause the application to terminate unexpectedly.
Affected products
- MongoDB C Driver before 1.30.10 and 2.5.3
Timeline
- 2026-09-10: disclosed
- 2026-09-10: patched