What is CVE-2021-20328?

CVE-2021-20328 is a medium-severity security vulnerability in org.mongodb:mongodb-driver (maven), affecting versions >= 3.11.0, <= 3.11.2. It is fixed in 3.11.3, 3.12.8, 4.0.6, 4.1.2, 4.2.1.

How severe is CVE-2021-20328?

CVE-2021-20328 has a CVSS score of 6.8 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.

Which packages are affected by CVE-2021-20328?

org.mongodb:mongodb-driver (maven) versions >= 3.11.0, = 4.0.0, = 3.11.0, = 4.0.0, <= 4.0.5.

Is there a fix for CVE-2021-20328?

Yes. CVE-2021-20328 is fixed in 3.11.3, 3.12.8, 4.0.6, 4.1.2, 4.2.1. Upgrade to this version or later.

Is CVE-2021-20328 exploitable, and should I be worried?

Whether CVE-2021-20328 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

What actually determines whether CVE-2021-20328 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

CVE-2021-20328 in org.mongodb:mongodb-driver

Q: How severe is CVE-2021-20328?

CVE-2021-20328 has a CVSS score of 6.8 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.

Q: Which packages are affected by CVE-2021-20328?

org.mongodb:mongodb-driver (maven) versions >= 3.11.0, = 4.0.0, = 3.11.0, = 4.0.0, <= 4.0.5.

Q: Is there a fix for CVE-2021-20328?

Yes. CVE-2021-20328 is fixed in 3.11.3, 3.12.8, 4.0.6, 4.1.2, 4.2.1. Upgrade to this version or later.

Q: Is CVE-2021-20328 exploitable, and should I be worried?

Whether CVE-2021-20328 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

Q: What actually determines whether CVE-2021-20328 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

Q: How do I fix CVE-2021-20328?

Upgrade: org.mongodb:mongodb-driver to 3.11.3 or later, org.mongodb:mongodb-driver to 3.12.8 or later, org.mongodb:mongodb-driver-sync to 4.0.6 or later, org.mongodb:mongodb-driver-sync to 4.1.2 or later, org.mongodb:mongodb-driver-sync to 4.2.1 or later, org.mongodb:mongo-java-driver to 3.11.3 or later, org.mongodb:mongo-java-driver to 3.12.8 or later, org.mongodb:mongodb-driver-legacy to 4.0.6 or later, org.mongodb:mongodb-driver-legacy to 4.1.2 or later, org.mongodb:mongodb-driver-legacy to 3.11.3 or later, org.mongodb:mongodb-driver-legacy to 3.12.8 or later, org.mongodb:mongodb-driver-sync to 3.12.8 or later, org.mongodb:mongodb-driver-sync to 3.11.3 or later, org.mongodb:mongodb-driver-legacy to 4.2.1 or later.

Summary

Improper Certificate Validation in MongoDB

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.

Impact

CVE-2021-20328 has a CVSS score of 6.8 (Medium). The vector is reachable from an adjacent network, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (3.11.3, 3.12.8, 4.0.6, 4.1.2, 4.2.1); upgrading removes the vulnerable code path.

Affected versions

org.mongodb:mongodb-driver (>= 3.11.0, <= 3.11.2) org.mongodb:mongodb-driver (>= 3.12.0, <= 3.12.7) org.mongodb:mongodb-driver-sync (>= 4.0.0, <= 4.0.5) org.mongodb:mongodb-driver-sync (>= 4.1.0, <= 4.1.1) org.mongodb:mongodb-driver-sync (= 4.2.0) org.mongodb:mongo-java-driver (>= 3.11.0, <= 3.11.2) org.mongodb:mongo-java-driver (>= 3.12.0, <= 3.12.7) org.mongodb:mongodb-driver-legacy (>= 4.0.0, <= 4.0.5) org.mongodb:mongodb-driver-legacy (>= 4.1.0, <= 4.1.1) org.mongodb:mongodb-driver-legacy (>= 3.11.0, <= 3.11.2) org.mongodb:mongodb-driver-legacy (>= 3.12.0, <= 3.12.7) org.mongodb:mongodb-driver-sync (>= 3.12.0, <= 3.12.7) org.mongodb:mongodb-driver-sync (>= 3.11.0, <= 3.11.2) org.mongodb:mongodb-driver-legacy (= 4.2.0)

Security releases

org.mongodb:mongodb-driver → 3.11.3 (maven) org.mongodb:mongodb-driver → 3.12.8 (maven) org.mongodb:mongodb-driver-sync → 4.0.6 (maven) org.mongodb:mongodb-driver-sync → 4.1.2 (maven) org.mongodb:mongodb-driver-sync → 4.2.1 (maven) org.mongodb:mongo-java-driver → 3.11.3 (maven) org.mongodb:mongo-java-driver → 3.12.8 (maven) org.mongodb:mongodb-driver-legacy → 4.0.6 (maven) org.mongodb:mongodb-driver-legacy → 4.1.2 (maven) org.mongodb:mongodb-driver-legacy → 3.11.3 (maven) org.mongodb:mongodb-driver-legacy → 3.12.8 (maven) org.mongodb:mongodb-driver-sync → 3.12.8 (maven) org.mongodb:mongodb-driver-sync → 3.11.3 (maven) org.mongodb:mongodb-driver-legacy → 4.2.1 (maven)

Kodem intelligence

Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.

Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.

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Remediation advice

Upgrade the following packages to resolve this vulnerability:

org.mongodb:mongodb-driver to 3.11.3 or later; org.mongodb:mongodb-driver to 3.12.8 or later; org.mongodb:mongodb-driver-sync to 4.0.6 or later; org.mongodb:mongodb-driver-sync to 4.1.2 or later; org.mongodb:mongodb-driver-sync to 4.2.1 or later; org.mongodb:mongo-java-driver to 3.11.3 or later; org.mongodb:mongo-java-driver to 3.12.8 or later; org.mongodb:mongodb-driver-legacy to 4.0.6 or later; org.mongodb:mongodb-driver-legacy to 4.1.2 or later; org.mongodb:mongodb-driver-legacy to 3.11.3 or later; org.mongodb:mongodb-driver-legacy to 3.12.8 or later; org.mongodb:mongodb-driver-sync to 3.12.8 or later; org.mongodb:mongodb-driver-sync to 3.11.3 or later; org.mongodb:mongodb-driver-legacy to 4.2.1 or later

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently Asked Questions

What is CVE-2021-20328? CVE-2021-20328 is a medium-severity security vulnerability in org.mongodb:mongodb-driver (maven), affecting versions >= 3.11.0, <= 3.11.2. It is fixed in 3.11.3, 3.12.8, 4.0.6, 4.1.2, 4.2.1.
How severe is CVE-2021-20328? CVE-2021-20328 has a CVSS score of 6.8 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
Which packages are affected by CVE-2021-20328?
- org.mongodb:mongodb-driver (maven) (versions >= 3.11.0, <= 3.11.2)
- org.mongodb:mongodb-driver-sync (maven) (versions >= 4.0.0, <= 4.0.5)
- org.mongodb:mongo-java-driver (maven) (versions >= 3.11.0, <= 3.11.2)
- org.mongodb:mongodb-driver-legacy (maven) (versions >= 4.0.0, <= 4.0.5)
Is there a fix for CVE-2021-20328? Yes. CVE-2021-20328 is fixed in 3.11.3, 3.12.8, 4.0.6, 4.1.2, 4.2.1. Upgrade to this version or later.
Is CVE-2021-20328 exploitable, and should I be worried? Whether CVE-2021-20328 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
What actually determines whether CVE-2021-20328 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
How do I fix CVE-2021-20328?
- Upgrade org.mongodb:mongodb-driver to 3.11.3 or later
- Upgrade org.mongodb:mongodb-driver to 3.12.8 or later
- Upgrade org.mongodb:mongodb-driver-sync to 4.0.6 or later
- Upgrade org.mongodb:mongodb-driver-sync to 4.1.2 or later
- Upgrade org.mongodb:mongodb-driver-sync to 4.2.1 or later
- Upgrade org.mongodb:mongo-java-driver to 3.11.3 or later
- Upgrade org.mongodb:mongo-java-driver to 3.12.8 or later
- Upgrade org.mongodb:mongodb-driver-legacy to 4.0.6 or later
- Upgrade org.mongodb:mongodb-driver-legacy to 4.1.2 or later
- Upgrade org.mongodb:mongodb-driver-legacy to 3.11.3 or later
- Upgrade org.mongodb:mongodb-driver-legacy to 3.12.8 or later
- Upgrade org.mongodb:mongodb-driver-sync to 3.12.8 or later
- Upgrade org.mongodb:mongodb-driver-sync to 3.11.3 or later
- Upgrade org.mongodb:mongodb-driver-legacy to 4.2.1 or later