Quick answers
- Is CVE-2026-106438 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-106438 being exploited in the wild.
- How severe is CVE-2026-106438?
- Medium severity, with a CVSS score of 4, published 8 October 2026.
- Which products and versions are affected?
- MongoDB C Driver before 1.30.13 and before 2.5.6.
- Is there a fix for CVE-2026-106438?
- Yes: fixed in C Driver 1.30.13, 2.5.6. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-106438 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-106438?
- 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.
How to fix
- Fixed in: C Driver 1.30.13, 2.5.6
Technical details
An incorrect precision validation check in Decimal128 string parsing allows over-precision inputs with leading zeros to be accepted instead of rejected, resulting in a parsed value that differs from the supplied input. This affects Extended JSON parsing and any code path accepting decimal strings. An attacker with the ability to supply untrusted decimal input can trigger incorrect numeric storage or computation.
Affected products
- MongoDB C Driver before 1.30.13 and before 2.5.6
Timeline
- 2026-10-08: disclosed