CVE-2026-96749
highpriority · track · 0EPSS 0.002 · 8 %ileDEUSEPSS · scored 2026-10-27
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
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.8–8.4
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (11)
Products and version ranges known to be affected.
advisories (3)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-3583MongoDB Treiber (Python Driver, PHP Driver, C Driver, Compass und Laravel): Mehrere SchwachstellenDeutsch2026-09-24csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in verschiedenen MongoDB Treibern (Python Driver, PHP Driver, C Driver, Compass und Laravel) ausnutzen, um einen Denial of Service Angriff durchzuführen, um Daten zu manipulieren, um beliebigen Programmcode auszuführen und um einen nicht näher spezifizierten Angriff durchzuführen.
- GHSA-v4x9-3549-crwvPyMongo: PYTHON-5996 Heap out-of-bounds write via signed size overflow in BSON document encoding2026-10-05ghsa · osvUS
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.
- PYSEC-2026-4296PyMongo: PYTHON-5996 Heap out-of-bounds write via signed size overflow in BSON document encoding2026-10-15vendor · osvUS
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.
also known as (2)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (3) nvd
External citations — patches, advisories, analysis.
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