Unbounded memory growth in MongoDB C# Driver BSON deserialization
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Attack requirements
- None
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-770.
Summary
The MongoDB C# Driver's BSON library from 2.0.0 before 3.13.0 has an uncontrolled resource consumption weakness (CWE-770) in deserialization of one BSON value type. Data derived from untrusted content is retained for the lifetime of the process with no limit. An unauthenticated remote party who can cause such content to be deserialized can drive unbounded memory growth, exhausting the application's memory and denying service. There is no impact to confidentiality or integrity.
Written with Claude Haiku 5.5 from the sources below · 2026-11-02
Description from the CNA
The MongoDB C# Driver's BSON library contains an uncontrolled resource consumption weakness in its deserialization handling of one BSON value type. An application that deserializes untrusted content with the library retains data derived from that content for the lifetime of the process, with no limit on how much accumulates. An unauthenticated remote party who can cause such content to be deserialized can drive unbounded memory growth, exhausting the host application's available memory and denying service. There is no impact to confidentiality or integrity, and no MongoDB server component is affected.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- 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
Upgrade the MongoDB C# Driver to version 3.13.0, the fixed version, which is not affected.
Written with Claude Haiku 5.5 from the sources below · 2026-11-02
- Fix · CNA C# Driver (MongoDB) Fixed in 3.13.0
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
MongoDB C# Driver 3.13.0
11 records Highest priority Priority HIGH 5 HIGH, 6 MEDIUM
Other records, highest priority first
- TI-2026-79432 BSON output corruption via out-of-range binary subtype in MongoDB C# DriverPriority HIGH 70
- TI-2026-79424 NoSQL command injection via mismatched BSON length in MongoDB C# DriverPriority HIGH 70
- TI-2026-79427 Authentication bypass via issuer-and-serial-only certificate equalityPriority HIGH 68
Timeline
- 2026-10-22 Threatist record created from CVE-2026-114644
- 2026-10-23 1 new reference · CNA
- 2026-10-23 Priority changed: MEDIUM → LOW
- 2026-11-02 CISA SSVC decision points changed
- 2026-11-02 Priority changed: LOW → HIGH
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-2026-79427 Authentication bypass via issuer-and-serial-only certificate equality CVSS 4.0HIGH 7.6
- TI-2026-79426 NoSQL injection in MongoDB C# Driver LINQ filter field names CVSS 4.0HIGH 7.2
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences