# CVE-2026-84963: mongo-c-driver: An incorrect numeric conversion in the JSON parsing component of the MongoDB C Driver's BSON library may cause an unu...

CVE-2026-84963 is fixed in mongo-c-driver on 1 platform by DEBIAN-CVE-2026-84963 (version 2.5.2-1), released September 10, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-84963
- Priority: Routine
- CVSS: n/a
- EPSS: 0.0031
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 3, 2026

## Description

An incorrect numeric conversion in the JSON parsing component of the MongoDB C Driver's BSON library may cause an unusually large text value to be silently shortened, or the corresponding field to be omitted, while the parsing operation still reports success and returns no error. An unauthenticated party who can supply the input processed by an application that uses this component may cause that application to hold data that does not match what was submitted, which may result in unintended alteration of data.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | mongo-c-driver Debian 14 | 2.5.2-1 | [DEBIAN-CVE-2026-84963](https://patchblox.com/security/data/fix/linux/debian-cve-2026-84963.md) | Sep 10, 2026 |

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Data as of 2026-11-09T07:25:28Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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