CVE-2021-20328

MongoDB Java driver client-side field level encryption not verifying KMS host name

Description

Specific versions of the Java driver that support client-side field level encryption (CSFLE) fail to perform correct host name verification on the KMS server’s certificate. This vulnerability in combination with a privileged network position active MITM attack could result in interception of traffic between the Java driver and the KMS service rendering Field Level Encryption ineffective. This issue was discovered during internal testing and affects all versions of the Java driver that support CSFLE. The Java async, Scala, and reactive streams drivers are not impacted. This vulnerability does not impact driver traffic payloads with CSFLE-supported key services originating from applications residing inside the AWS, GCP, and Azure network fabrics due to compensating controls in these environments. This issue does not impact driver workloads that don’t use Field Level Encryption.

Category

6.4
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.05%
Vendor Advisory mongodb.org
Affected: MongoDB Inc. mongo-java-driver
Affected: MongoDB Inc. mongodb-driver
Affected: MongoDB Inc. mongodb-driver-sync
Affected: MongoDB Inc. mongodb-driver-legacy
Published at:
Updated at:

References

Link Tags
https://jira.mongodb.org/browse/JAVA-4017 issue tracking patch vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-20328?
CVE-2021-20328 has been scored as a medium severity vulnerability.
How to fix CVE-2021-20328?
To fix CVE-2021-20328, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-20328 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-20328 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-20328?
CVE-2021-20328 affects MongoDB Inc. mongo-java-driver, MongoDB Inc. mongodb-driver, MongoDB Inc. mongodb-driver-sync, MongoDB Inc. mongodb-driver-legacy.
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