CVE-2026-59969

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.

Affected Software

VendorProductVersion RangeStatus
Apache Software FoundationApache ZooKeeper3.9.0 <= 3.9.5affected
Apache Software FoundationApache ZooKeeper3.8.0 <= 3.8.6affected

Weaknesses

  • CWE-297: CWE-297 Improper Validation of Certificate with Host Mismatch

ADP Enrichment

CVE Program Container

Additional References

References