Uninitialized memory in MongoDB C Driver GridFS can expose credentials
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- Present
- Impact type
- Information disclosure
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- No fix listed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-908 and the CVSS impact.
Summary
The MongoDB C Driver from 1.25.0 through 1.30.14 and from 2.0.0 through 2.5.7 is affected. Its legacy GridFS file handling treats uninitialized process memory as valid file content (CWE-908) and stores it on the server. A database user with ordinary write access to a shared storage area can arrange for an application to later append to such a file, which writes that memory into records the same user can read, possibly exposing sensitive data from the application's process, including credentials.
Written with Claude Haiku 5.5 from the sources below · 2026-11-04
Description from the CNA
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
The sources list no fixed version for MongoDB C Driver.
Written with Claude Haiku 5.5 from the sources below · 2026-11-04
Vendor assessments
Timeline
- 2026-11-03 Threatist record created from CVE-2026-120684
- 2026-11-03 Title updated · CNA
- 2026-11-03 CISA SSVC decision points changed
- 2026-11-03 Priority changed: MEDIUM → LOW
- 2026-11-04 Affected versions changed · Red Hat
- 2026-11-04 CVSS score added · Red Hat
References
More MongoDB vulnerabilities
- TI-2019-08023 Code injection in mongo-express KEVCVSS 3.1CRITICAL 9.9
- TI-2025-13542 Zlib compressed protocol header length confusion may allow memory read KEVCVSS 4.0HIGH 8.7
- TI-2026-79432 BSON output corruption via out-of-range binary subtype in MongoDB C# Driver CVSS 4.0MEDIUM 6.9
- TI-2026-79424 NoSQL command injection via mismatched BSON length in MongoDB C# Driver CVSS 4.0MEDIUM 6.9
- TI-2026-79422 Unbounded memory growth in MongoDB C# Driver BSON deserialization CVSS 4.0HIGH 8.2
- TI-2026-79427 Authentication bypass via issuer-and-serial-only certificate equality CVSS 4.0HIGH 7.6
Sources
- CVE-2026-120684 · CVE Program
- CVE-2026-120684 · NVD
- FIRST EPSS
- CVE-2026-120684 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences