CVE-2021-20327
MongoDB Node.js client side field level encryption library may not be validating KMS certificate
A specific version of the Node.js mongodb-client-encryption module does not perform correct validation of 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 Node.js driver and the KMS service rendering client-side field level encryption (CSFLE) ineffective. This issue was discovered during internal testing and affects mongodb-client-encryption module version 1.2.0, which was available from 2021-Jan-29 and deprecated in the NPM Registry on 2021-Feb-04. This vulnerability does not impact driver traffic payloads with CSFLE-supported key services from applications residing inside the AWS, GCP, and Azure nework fabrics due to compensating controls in these environments. This issue does not impact driver workloads that don’t use Field Level Encryption. This issue affect MongoDB Node.js Driver mongodb-client-encryption module version 1.2.0
Attack profile
How easy it is to exploit
- Attack vector
- Adjacent network
- Complexity
- High
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
MongoDB Node.js client side field level encryption library may not be validating KMS certificate
A specific version of the Node.js mongodb-client-encryption module does not perform correct validation of 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 Node.js driver and the KMS service rendering client-side field level encryption (CSFLE) ineffective. This issue was discovered during internal testing and affects mongodb-client-encryption module version 1.2.0, which was available from 2021-Jan-29 and deprecated in the NPM Registry on 2021-Feb-04. This vulnerability does not impact driver traffic payloads with CSFLE-supported key services from applications residing inside the AWS, GCP, and Azure nework fabrics due to compensating controls in these environments. This issue does not impact driver workloads that don’t use Field Level Encryption. This issue affect MongoDB Node.js Driver mongodb-client-encryption module version 1.2.0
- Record
CVE-2021-20327- CVSS 3.1
- 6.4 Medium
CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N - Weakness
- CWE-295
- Updated
- 2026-11-02
EUVDEUVD-2021-0871
A specific version of the Node.js mongodb-client-encryption module does not perform correct validation of 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 Node.js driver and the KMS service rendering client-side field level encryption (CSFLE) ineffective. This issue was discovered during internal testing and affects mongodb-client-encryption module version 1.2.0, which was available from 2021-Jan-29 and deprecated in the NPM Registry on 2021-Feb-04. This vulnerability does not impact driver traffic payloads with CSFLE-supported key services from applications residing inside the AWS, GCP, and Azure nework fabrics due to compensating controls in these environments. This issue does not impact driver workloads that don’t use Field Level Encryption. This issue affect MongoDB Node.js Driver mongodb-client-encryption module version 1.2.0
- Record
EUVD-2021-0871- CVSS 3.1
- 6.4 Medium
CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-rjmf-p882-645m
mongodb-client-encryption vulnerable to Improper Certificate Validation
A specific version of the Node.js mongodb-client-encryption module does not perform correct validation of 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 Node.js driver and the KMS service rendering client-side field level encryption (CSFLE) ineffective. This issue was discovered during internal testing and affects mongodb-client-encryption module version 1.2.0, which was available from 2021-Jan-29 and deprecated in the NPM Registry on 2021-Feb-04. This vulnerability does not impact driver traffic payloads with CSFLE-supported key services from applications residing inside the AWS, GCP, and Azure nework fabrics due to compensating controls in these environments. This issue does not impact driver workloads that don’t use Field Level Encryption. This issue affect MongoDB Node.js Driver mongodb-client-encryption module version 1.2.0
- Record
GHSA-rjmf-p882-645m- CVSS 3.1
- 6.8 Medium
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N - Weakness
- CWE-295
- Updated
- 2026-11-02
NVD
A specific version of the Node.js mongodb-client-encryption module does not perform correct validation of 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 Node.js driver and the KMS service rendering client-side field level encryption (CSFLE) ineffective. This issue was discovered during internal testing and affects mongodb-client-encryption module version 1.2.0, which was available from 2021-Jan-29 and deprecated in the NPM Registry on 2021-Feb-04. This vulnerability does not impact driver traffic payloads with CSFLE-supported key services from applications residing inside the AWS, GCP, and Azure nework fabrics due to compensating controls in these environments. This issue does not impact driver workloads that don’t use Field Level Encryption. This issue affect MongoDB Node.js Driver mongodb-client-encryption module version 1.2.0
- Record
CVE-2021-20327- CVSS 3.1
- 6.4 Medium
CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N - CVSS 3.1
- 6.8 Medium
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N - CVSS 2.0
- 4.3 Medium
AV:A/AC:M/Au:N/C:P/I:P/A:N - Weakness
- CWE-295
- Updated
- 2026-11-02
OSV
A specific version of the Node.js mongodb-client-encryption module does not perform correct validation of 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 Node.js driver and the KMS service rendering client-side field level encryption (CSFLE) ineffective. This issue was discovered during internal testing and affects mongodb-client-encryption module version 1.2.0, which was available from 2021-Jan-29 and deprecated in the NPM Registry on 2021-Feb-04. This vulnerability does not impact driver traffic payloads with CSFLE-supported key services from applications residing inside the AWS, GCP, and Azure nework fabrics due to compensating controls in these environments. This issue does not impact driver workloads that don’t use Field Level Encryption. This issue affect MongoDB Node.js Driver mongodb-client-encryption module version 1.2.0
- Record
CVE-2021-20327- CVSS 3.1
- 6.8 Medium
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N - Updated
- 2026-11-02
OSVGHSA-rjmf-p882-645m
mongodb-client-encryption vulnerable to Improper Certificate Validation
A specific version of the Node.js mongodb-client-encryption module does not perform correct validation of 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 Node.js driver and the KMS service rendering client-side field level encryption (CSFLE) ineffective. This issue was discovered during internal testing and affects mongodb-client-encryption module version 1.2.0, which was available from 2021-Jan-29 and deprecated in the NPM Registry on 2021-Feb-04. This vulnerability does not impact driver traffic payloads with CSFLE-supported key services from applications residing inside the AWS, GCP, and Azure nework fabrics due to compensating controls in these environments. This issue does not impact driver workloads that don’t use Field Level Encryption. This issue affect MongoDB Node.js Driver mongodb-client-encryption module version 1.2.0
- Record
GHSA-rjmf-p882-645m- CVSS 3.1
- 6.8 Medium
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N - Weakness
- CWE-295
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
mongodb-client-encryptionnpm | 1.2.0 to 1.2.0 | 1.2.1 |
mongodb-client-encryptionnpm | 1.2.0 up to 1.2.1 | 1.2.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | ||
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-20327 is a medium vulnerability (CVSS 6.4) in Mongodb Inc. Node.js Driver Mongodb-client-encryption Module, published February 25, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.20%, the 10th percentile. Fixed in mongodb-client-encryption 1.2.1.