High severity · published Apr 13, 2026
CVE-2026-6231
bson_validate may skip validation when processing certain inputs
7.5
CVSS
0.2%
EPSS
No
On KEV
Description
The bson_validate function may return early on specific inputs and incorrectly report success. This behavior could result in skipping validation for BSON data, allowing malformed or invalid UTF-8 sequences to bypass validation and be processed incorrectly. The issue may affect applications that rely on these functions to validate untrusted BSON data before further processing. This issue affects MongoDB C Driver versions prior to 1.30.5, MongoDB C Driver version 2.0.0 and MongoDB C Driver version 2.0.1
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 8% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CD
C Driver · MongoDB Inc.
1.0 before 1.30.5; 2.0 before 2.0.2 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-6231
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-6231
Issue Tracking
https://jira.mongodb.org/browse/CDRIVER-6017
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