CVE-2021-20331

CVE-2021-20331 is a medium-severity vulnerability in Mongodb C# Driver with a CVSS 3.x base score of 4.2. 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-200.

Key facts

Description

Specific versions of the MongoDB C# Driver may erroneously publish events containing authentication-related data to a command listener configured by an application. The published events may contain security-sensitive data when commands such as "saslStart", "saslContinue", "isMaster", "createUser", and "updateUser" are executed. Without due care, an application may inadvertently expose this authenticated-related information, e.g., by writing it to a log file. This issue only arises if an application enables the command listener feature (this is not enabled by default). This issue affects the MongoDB C# Driver v2.12 versions prior to and including 2.12.1.

Frequently asked questions

What is CVE-2021-20331?
Specific versions of the MongoDB C# Driver may erroneously publish events containing authentication-related data to a command listener configured by an application. The published events may contain security-sensitive data when commands such as "saslStart", "saslContinue", "isMaster", "createUser", and "updateUser" are executed. Without due care, an application may inadvertently expose this authenticated-related information, e.g., by writing it to a log file. This issue only arises if an application enables the command listener feature (this is not enabled by default). This issue affects the MongoDB C# Driver v2.12 versions prior to and including 2.12.1.
How severe is CVE-2021-20331?
CVE-2021-20331 has a CVSS 3.x base score of 4.2, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-20331 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20331?
CVE-2021-20331 primarily affects Mongodb C# Driver. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-20331?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-20331 published?
CVE-2021-20331 was published on 2021-05-13 and last updated on 2026-06-17.

References

Affected products (2)

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