CVE-2026-96749

Description

An integer overflow in the BSON document encoding component of the MongoDB Python Driver's bundled native extension may occur when a single document is built from an unusually large amount of caller-supplied data. Size arithmetic is performed in a signed 32-bit type, and the guard meant to catch the overflow is written in a form whose behavior is not defined by the C language standard. A party with no privileges who can place a very large value into data that an application encodes may, depending on how the native extension was built, cause a write outside the bounds of an allocated buffer inside the application's own process.

CVSS Vector

References

• https://github.com/mongodb/mongo-python-driver/blob/4.18.2/doc/changelog.rst
• https://github.com/mongodb/mongo-python-driver/releases/tag/4.18.2
• https://github.com/mongodb/mongo-python-driver/security/advisories/GHSA-v4x9-3549-crwv