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TI-2026-69710 Aliases CVE-2026-106431

One-byte heap buffer overflow in MongoDB C Driver BSON bulk writer

Priority LOW 25CWE-787Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
None · Low · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

The MongoDB C Driver from 0.5.0 before 1.30.13 and from 2.0.0 before 2.5.6 contains an off-by-one error in its BSON bulk document writer. When a document ends at a specific buffer boundary, the writer writes one zero byte past a heap allocation, which is a CWE-787 out-of-bounds write. An actor who can influence the size of documents serialized by an embedding application can corrupt adjacent process memory or terminate the process. Exploitation requires the application to use the BSON bulk-writer API and produce a precise cumulative document size.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Description from the CNA

An off-by-one error in the BSON bulk document writer in the MongoDB C Driver can write one zero byte immediately past a heap allocation when a document ends at a specific buffer boundary. An actor who can influence the size of documents serialized by an embedding application can corrupt adjacent process memory or terminate the process. Reaching this issue requires the application to use the BSON bulk-writer API and produce a precise cumulative document size.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00097 0th percentileScored 2026-11-07
Fix Fixed C Driver (MongoDB): 1.30.13, 2.5.6

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

VendorProductAffected versionsFixed inStatusSource
MongoDBC Driver0.5.0 to before 1.30.13; 2.0.0 to before 2.5.61.30.13, 2.5.6Patch availableCNA
  • C Driver VendorMongoDB Affected 0.5.0 to before 1.30.13; 2.0.0 to before 2.5.6 Fixed in 1.30.13, 2.5.6 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:mongodb:c_driver:*:*:*:*:*:*:*:*——MongoDB
  • cpe:2.3:a:mongodb:c_driver:*:*:*:*:*:*:*:* Versions — — ·MongoDB

Remediation

Upgrade the MongoDB C Driver to version 1.30.13 or 2.5.6, which fix this issue. Red Hat lists one product as not affected.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

  • Fix · CNA C Driver (MongoDB) Fixed in 1.30.13, 2.5.6

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    MongoDB C Driver 1.30.13, 2.5.6

    3 records Highest priority Priority LOW 3 LOW

    Other records, highest priority first

    • TI-2026-69713 Out-of-bounds memory access in MongoDB C Driver BSON buffersPriority LOW 25
    • TI-2026-69714 Silent Decimal128 value corruption in MongoDB C DriverPriority LOW 22
    Show all 3 records →

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-09 Threatist record created from CVE-2026-106431
  2. 2026-10-10 Affected versions changed · Red Hat
  3. 2026-10-10 CVSS score added · Red Hat

References

Other 1

  • 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
See all 376 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences