{"id":"CVE-2026-59969","state":"PUBLISHED","title":"Apache ZooKeeper: Improper validation of certificate with host mismatch in FIPS mode","description":"Apache ZooKeeper quorum TLS fails to enforce peer hostname verification in FIPS-mode deployments. When sslQuorum=true, zookeeper.fips-mode=true, ssl.quorum.hostnameVerification=true, and ssl.quorum.clientHostnameVerification=true are enabled, the Java SSLSocket quorum path accepts a CA-trusted peer certificate whose SAN does not match the connected host. A malicious or misissued peer certificate can therefore join quorum traffic, participate in leader election, and enter replication flows.\n\n\n\nUsers are recommended to upgrade to version 3.8.7 or 3.9.6, which fixes the issue.","publishedAt":"2026-09-16T09:27:00.726Z","updatedAt":"2026-09-17T19:17:01.444Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","source":"CISA-ADP"},"assigner":"apache","products":["Apache Software Foundation Apache ZooKeeper"],"affected":[{"vendor":"Apache Software Foundation","product":"Apache ZooKeeper","packageName":"org.apache.zookeeper:zookeeper","packageURL":"pkg:maven/org.apache.zookeeper/zookeeper","defaultStatus":"unaffected","versions":[{"version":"3.9.0","status":"affected","lessThanOrEqual":"3.9.5","versionType":"maven"},{"version":"3.8.0","status":"affected","lessThanOrEqual":"3.8.6","versionType":"maven"}],"collectionURL":"https://repo.maven.apache.org/maven2"}],"references":["https://lists.apache.org/thread/qf9kwsgtgbgtvwls6f41281846xg0rss","http://www.openwall.com/lists/oss-security/2026/09/15/4"],"weaknesses":["CWE-297"],"ingestedAt":"2026-10-29T20:12:32.778Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/59xxx/CVE-2026-59969.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-59969","state":"PUBLISHED","datePublished":"2026-09-16T09:27:00.726Z","dateUpdated":"2026-09-17T19:17:01.444Z","assignerShortName":"apache","assignerOrgId":"f0158376-9dc2-43b6-827c-5f631a4d8d09","dateReserved":"2026-07-07T18:50:40.959Z"},"containers":{"cna":{"title":"Apache ZooKeeper: Improper validation of certificate with host mismatch in FIPS mode","descriptions":[{"lang":"en","value":"Apache ZooKeeper quorum TLS fails to enforce peer hostname verification in FIPS-mode deployments. When sslQuorum=true, zookeeper.fips-mode=true, ssl.quorum.hostnameVerification=true, and ssl.quorum.clientHostnameVerification=true are enabled, the Java SSLSocket quorum path accepts a CA-trusted peer certificate whose SAN does not match the connected host. A malicious or misissued peer certificate can therefore join quorum traffic, participate in leader election, and enter replication flows.\n\n\n\nUsers are recommended to upgrade to version 3.8.7 or 3.9.6, which fixes the issue."}],"affected":[{"vendor":"Apache Software Foundation","product":"Apache ZooKeeper","packageName":"org.apache.zookeeper:zookeeper","packageURL":"pkg:maven/org.apache.zookeeper/zookeeper","defaultStatus":"unaffected","versions":[{"version":"3.9.0","status":"affected","lessThanOrEqual":"3.9.5","versionType":"maven"},{"version":"3.8.0","status":"affected","lessThanOrEqual":"3.8.6","versionType":"maven"}],"collectionURL":"https://repo.maven.apache.org/maven2"}],"references":[{"url":"https://lists.apache.org/thread/qf9kwsgtgbgtvwls6f41281846xg0rss","tags":["vendor-advisory"]}],"metrics":[{"other":{"type":"Textual description of severity","content":{"text":"important"}},"scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-297","description":"CWE-297 Improper Validation of Certificate with Host Mismatch","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"apache","orgId":"f0158376-9dc2-43b6-827c-5f631a4d8d09","dateUpdated":"2026-09-16T09:27:00.726Z"},"source":{"discovery":"UNKNOWN"},"credits":[{"lang":"en","value":"Erichen <chenyoulong20g@ict.ac.cn>","type":"reporter"}],"x_generator":{"engine":"Vulnogram 0.2.0"}},"adp":[{"title":"CVE Program Container","references":[{"url":"http://www.openwall.com/lists/oss-security/2026/09/15/4"}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2026-09-16T10:11:44.041Z"}},{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":7.5,"attackVector":"NETWORK","baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","integrityImpact":"HIGH","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"NONE","privilegesRequired":"NONE","confidentialityImpact":"NONE"}},{"other":{"type":"ssvc","content":{"timestamp":"2026-09-17T19:16:38.006304Z","id":"CVE-2026-59969","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-17T19:17:01.444Z"}}]}}}