{"cve":"CVE-2021-20328","nvd":{"published":"2021-02-25T17:15:28.303","modified":"2026-06-17T03:33:40.913","status":"Modified","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","score":6.8},"cwes":["CWE-295"],"references":["https://jira.mongodb.org/browse/JAVA-4017","https://jira.mongodb.org/browse/JAVA-4017"],"products":["mongodb:java_driver","quarkus:quarkus"],"source":"nvd","synced_at":"2026-10-19T21:15:50.279857260+00:00"},"epss":{"cve":"CVE-2021-20328","score":0.00436,"percentile":0.37874,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-rghw-6px2-fgwc","url":"https://osv.dev/vulnerability/GHSA-rghw-6px2-fgwc","summary":"Improper Certificate Validation in MongoDB","modified":"2024-02-16T08:11:17.848383Z","packages":[{"ecosystem":"Maven","name":"org.mongodb:mongodb-driver","purl":"pkg:maven/org.mongodb/mongodb-driver","ranges":[">=3.11.0 <3.11.3"],"fixed":["3.11.3"]},{"ecosystem":"Maven","name":"org.mongodb:mongodb-driver","purl":"pkg:maven/org.mongodb/mongodb-driver","ranges":[">=3.12.0 <3.12.8"],"fixed":["3.12.8"]},{"ecosystem":"Maven","name":"org.mongodb:mongodb-driver-sync","purl":"pkg:maven/org.mongodb/mongodb-driver-sync","ranges":[">=4.0.0 <4.0.6"],"fixed":["4.0.6"]},{"ecosystem":"Maven","name":"org.mongodb:mongodb-driver-sync","purl":"pkg:maven/org.mongodb/mongodb-driver-sync","ranges":[">=4.1.0 <4.1.2"],"fixed":["4.1.2"]},{"ecosystem":"Maven","name":"org.mongodb:mongodb-driver-sync","purl":"pkg:maven/org.mongodb/mongodb-driver-sync","ranges":[">=4.2.0 <4.2.1"],"fixed":["4.2.1"]},{"ecosystem":"Maven","name":"org.mongodb:mongo-java-driver","purl":"pkg:maven/org.mongodb/mongo-java-driver","ranges":[">=3.11.0 <3.11.3"],"fixed":["3.11.3"]},{"ecosystem":"Maven","name":"org.mongodb:mongo-java-driver","purl":"pkg:maven/org.mongodb/mongo-java-driver","ranges":[">=3.12.0 <3.12.8"],"fixed":["3.12.8"]},{"ecosystem":"Maven","name":"org.mongodb:mongodb-driver-legacy","purl":"pkg:maven/org.mongodb/mongodb-driver-legacy","ranges":[">=4.0.0 <4.0.6"],"fixed":["4.0.6"]},{"ecosystem":"Maven","name":"org.mongodb:mongodb-driver-legacy","purl":"pkg:maven/org.mongodb/mongodb-driver-legacy","ranges":[">=4.1.0 <4.1.2"],"fixed":["4.1.2"]},{"ecosystem":"Maven","name":"org.mongodb:mongodb-driver-legacy","purl":"pkg:maven/org.mongodb/mongodb-driver-legacy","ranges":[">=3.11.0 <3.11.3"],"fixed":["3.11.3"]},{"ecosystem":"Maven","name":"org.mongodb:mongodb-driver-legacy","purl":"pkg:maven/org.mongodb/mongodb-driver-legacy","ranges":[">=3.12.0 <3.12.8"],"fixed":["3.12.8"]},{"ecosystem":"Maven","name":"org.mongodb:mongodb-driver-sync","purl":"pkg:maven/org.mongodb/mongodb-driver-sync","ranges":[">=3.12.0 <3.12.8"],"fixed":["3.12.8"]},{"ecosystem":"Maven","name":"org.mongodb:mongodb-driver-sync","purl":"pkg:maven/org.mongodb/mongodb-driver-sync","ranges":[">=3.11.0 <3.11.3"],"fixed":["3.11.3"]},{"ecosystem":"Maven","name":"org.mongodb:mongodb-driver-legacy","purl":"pkg:maven/org.mongodb/mongodb-driver-legacy","ranges":[">=4.2.0 <4.2.1"],"fixed":["4.2.1"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}