# CVE-2026-107324: MongoDB Go Driver integer overflow in BSON handling

Source: https://junglewise.ai/threats/cve-2026-107324-an-integer-overflow-in-bson-value-length-handling-in-the-mongodb  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-08. Updated: 2026-10-16  
License: CC BY 4.0 with a link back

CVE-2026-107324 · Severity: medium · CVSS 5.9 · Published 2026-10-08

The MongoDB Go Driver, a library that applications use to connect to MongoDB databases, contains a flaw in how it processes BSON documents (the binary format MongoDB uses). An attacker who sends a specially crafted BSON document to an application can cause it to crash, resulting in a denial of service. This affects applications using the driver directly or through the bsoncore library to parse untrusted data.

Technologies: [MongoDB Go Driver](https://junglewise.ai/threats/technologies/go-driver). Vendors: [MongoDB](https://junglewise.ai/threats/vendors/mongodb).

## Quick answers

**Is CVE-2026-107324 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-107324 being exploited in the wild.

**How severe is CVE-2026-107324?** Medium severity, with a CVSS score of 5.9, published 8 October 2026.

**Which products and versions are affected?** MongoDB Go Driver before 2.9.0.

**Is there a fix for CVE-2026-107324?** Yes: fixed in 2.9.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-107324 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-107324?** Check whether you run MongoDB Go 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 2.9.0

## Technical details

An integer overflow occurs in the bsoncore.valueLength function when processing BSON binary values with malformed length fields. When a value length equals INT32_MAX and the function adds 4 bytes for length encoding, the result overflows. If a length becomes negative after processing, the function does not properly reject it, potentially causing a runtime panic when the application attempts to validate or access the document. The vulnerability requires the application to handle BSON bytes directly or receive them from an untrusted source.

## Affected products

- MongoDB Go Driver before 2.9.0

## Timeline

- 2026-10-08: disclosed
- 2026-08-25: patched

## References

- [https://jira.mongodb.org/browse/GODRIVER-4102](https://jira.mongodb.org/browse/GODRIVER-4102)

## Related threats

- [MongoDB Go Driver BSON array validation out-of-bounds](https://junglewise.ai/threats/cve-2026-107325-improper-validation-of-a-bson-array-length-in-the-mongodb-go)
- [MongoDB Go Driver improper neutralization in GridFS delete](https://junglewise.ai/threats/cve-2026-88031-mongodb-go-driver-improper-neutralization-in-gridfs-delete)
- [MongoDB Go Driver namespace injection in BulkWrite](https://junglewise.ai/threats/cve-2026-81521-mongodb-go-driver-namespace-injection-in-bulkwrite)
- [MongoDB mongo-go-driver heap out-of-bounds read in GSSAPI error handling](https://junglewise.ai/threats/cve-2026-2303-mongodb-mongo-go-driver-heap-out-of-bounds-read-in-gssapi-error)