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CVE-2026-59969 (GCVE-0-2026-59969)

Vulnerability from cvelistv5 – Published: 2026-09-16 09:27 – Updated: 2026-09-16 10:11
VLAI
Title
Apache ZooKeeper: Improper validation of certificate with host mismatch in FIPS mode
Summary
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. Users are recommended to upgrade to version 3.8.7 or 3.9.6, which fixes the issue.
Severity
No CVSS data available.
CWE
  • CWE-297 - Improper Validation of Certificate with Host Mismatch
Impacted products
Vendor Product Version CPE status
Apache Software Foundation Apache ZooKeeper Affected: 3.9.0 , ≤ 3.9.5 (maven)
Affected: 3.8.0 , ≤ 3.8.6 (maven)
guessed Create a notification for this product.
Show details on NVD website

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