CVE-2026-106431
One-byte heap buffer overflow in BSON bulk document writer in MongoDB C Driver
CVSS Score
5.7
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-787 |
| Vendor | mongodb |
| Product | c driver |
| Ecosystems | |
| Industries | Technology |
| Published | Oct 8, 2026 |
| Last Updated | Oct 8, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H Attack Vector
Local
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
High
Affected Versions
MongoDB / C Driver
0.5.0 < 1.30.13 2.0.0 < 2.5.6