# CVE-2026-13077: Out-of-Bounds Heap Read in BSON CodeWScope Element Parsing via Malformed BSONColumn Data

> CVE-2026-13077: Out-of-Bounds Heap Read in BSON CodeWScope Element Parsing via Malformed BSONColumn Data. CVSS 7.1 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-13077
Last updated: 2026-10-24T13:10:00Z

- Published: 2026-07-22 19:12 UTC · Updated: 2026-10-24 13:10 UTC · Assigner: mongodb
- CVSS: 7.1 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H
- EPSS: 0.42%, 36th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-125

## Description

A missing bounds check in the BSON CodeWScope element accessors allows an attacker to trigger an out-of-bounds heap read via a crafted aggregation pipeline. The vulnerability can be exploited by an authenticated user by generating a malformed BSONColumn data containing a CodeWScope element, bypassing wire-level BSON validation. When the forged element is decompressed, the unchecked size value is used in pointer arithmetic, causing either a server crash or disclosure of adjacent heap memory contents.

## Affected vendors and products

- MongoDB: MongoDB Server

## Tracked companies

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

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-13077)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-13077)
- [https://jira.mongodb.org/browse/SERVER-129103](https://jira.mongodb.org/browse/SERVER-129103)

---

_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/)_


---
Canonical: https://rewindex.com/cve/CVE-2026-13077 · Markdown: https://rewindex.com/cve/CVE-2026-13077.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-13077 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:11:20.858Z