# CVE-2026-106432: Heap buffer overflow via 32-bit string-length truncation in MongoDB PHP Driver

> CVE-2026-106432: Heap buffer overflow via 32-bit string-length truncation in MongoDB PHP Driver. CVSS 3.6 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-106432
Last updated: 2026-10-13T20:09:23Z

- Published: 2026-10-08 19:02 UTC · Updated: 2026-10-13 20:09 UTC · Assigner: mongodb
- CVSS: 3.6 (CVSS 3.1) · Severity: Low · Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:L
- EPSS: 0.17%, 6th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-681

## Description

The BSON encoder in the MongoDB PHP Driver converts a string length to a 32-bit value without validation. When an affected application encodes a string near 4 GiB, the allocation size can wrap while the copy operation uses the original length. The resulting heap buffer overflow can corrupt process memory or terminate the PHP process. Reaching this issue requires a non-default runtime configuration that permits multi-gigabyte values. No MongoDB server interaction is required.

## Affected vendors and products

- MongoDB: PHP Driver

## Tracked companies

- [MongoDB Atlas](https://rewindex.com/company/mongodb-atlas.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-106432)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-106432)
- [https://jira.mongodb.org/browse/PHPC-2741](https://jira.mongodb.org/browse/PHPC-2741)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-106432 · Markdown: https://rewindex.com/cve/CVE-2026-106432.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-106432 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T04:05:27.044Z