# CVE-2026-120684: MongoDB C Driver GridFS gap lets a shared writer recover a protected client's password

Status: published. Published: 2026-11-03. Updated: 2026-11-03.

A memory-initialization flaw in the legacy GridFS file handling of the MongoDB C Driver can cause uninitialized process memory to be treated as valid file content and stored on the server. A database user holding ordinary write access to a shared storage area can arrange conditions under which an application later appends to such a file and writes that memory into records the same user is permitted to read, which may result in unintended disclosure of sensitive information from the application's process, including credentials.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- MongoDB / C Driver: ≥ 1.25.0; ≤ 1.30.14 (affected, semver); ≥ 2.0.0; ≤ 2.5.7 (affected, semver). Source: CNA: mongodb

## Severity and prioritization

- CVSS 4.0: 6 (medium); CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N; source: CNA: mongodb

- CVSS 3.1: 6.5 (medium); CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N; source: CNA: mongodb

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-908

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://jira.mongodb.org/browse/CDRIVER-6508 (CNA: mongodb)

## Provenance

- CNA: mongodb: https://www.cve.org/CVERecord?id=CVE-2026-120684; retrieved 2026-11-03; source updated 2026-11-03

Revision: eaad941ec98da2ab9cd3ad401dc23c90c8fb5fccdc26da29e2a0bcf598b0d127

Canonical: https://y2.dev/cve/CVE-2026-120684

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