How severe is CVE-2026-6231?

CVE-2026-6231 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2026-6231 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-6231?

CVE-2026-6231 affects Mongodb C Driver. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-6231?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-6231 have an EU (EUVD) identifier?

Yes. CVE-2026-6231 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22023.

When was CVE-2026-6231 published?

CVE-2026-6231 was published on 2026-04-13 and last updated on 2026-06-17.

CVE-2026-6231

CVE-2026-6231 is a medium-severity vulnerability in Mongodb C Driver with a CVSS 3.x base score of 4.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
CVSS v4: 5.3
EPSS exploit prediction: 0% (8th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-22023
Weakness: CWE-20
Affected product: Mongodb C Driver
Published: 2026-04-13
Last modified: 2026-06-17

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

Frequently asked questions

What is CVE-2026-6231?: 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
How severe is CVE-2026-6231?: CVE-2026-6231 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2026-6231 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-6231?: CVE-2026-6231 affects Mongodb C Driver. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-6231?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-6231 have an EU (EUVD) identifier?: Yes. CVE-2026-6231 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22023.
When was CVE-2026-6231 published?: CVE-2026-6231 was published on 2026-04-13 and last updated on 2026-06-17.

References

https://jira.mongodb.org/browse/CDRIVER-6017

Affected products (1)

cpe:2.3:a:mongodb:c_driver:*:*:*:*:*:mongodb:*:*

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