ZeroHour

Search: “zookeeper”

5 stories in the last 24h

CVE-2026-84501: Apache ZooKeeper: Operational log forgery via newline injection in EnsembleAuthenticationProvider

Unauthenticated attackers can forge Apache ZooKeeper operational log lines via newline injection in crafted ensemble authentication requests.

CVE-2026-84501 (moderate severity) affects Apache ZooKeeper 3.9.0-3.9.5 and 3.8.0-3.8.6. An unauthenticated attacker can inject arbitrary fake log lines into the operational log by sending a crafted add_auth("ensemble", ...) request containing newline characters. The forged entries could mislead operators or corrupt log-based monitoring and forensics.

CVE-2026-84439: Apache ZooKeeper: Audit log injection via unsanitized output from multiple sources

Apache ZooKeeper audit logs are vulnerable to arbitrary field injection by unauthenticated attackers via tab characters in digest auth requests.

CVE-2026-84439 (important severity) affects Apache ZooKeeper 3.9.0-3.9.5 and 3.8.0-3.8.6 when audit logging is enabled (zookeeper.audit.enable=true). An unauthenticated attacker can inject arbitrary fields into the audit log by sending a digest authentication request with embedded tab characters, undermining audit trail integrity and potentially enabling log-analysis evasion or spoofing.

CVE-2026-59969: Apache ZooKeeper: Improper validation of certificate with host mismatch in FIPS mode

CVE-2026-59969: Apache ZooKeeper quorum TLS skips peer hostname verification in FIPS-mode deployments, enabling potential server-to-server impersonation.

Apache ZooKeeper versions 3.8.0-3.8.6 and 3.9.0-3.9.5 fail to enforce peer hostname verification for quorum TLS when FIPS mode is enabled with sslQuorum, zookeeper.fips-mode, and hostname verification settings turned on. The flaw is rated important and could allow an attacker to impersonate a quorum peer via certificate host mismatch. Users should upgrade to fixed versions.

CVE-2026-59739: Apache ZooKeeper: Information disclosure via SetWatches reconnect replay

CVE-2026-59739: Apache ZooKeeper missing ACL check in SetWatches reconnect replay lets attackers discover ACL-restricted znode paths.

Apache ZooKeeper versions 3.8.0-3.8.6 and 3.9.0-3.9.5 contain a critical information disclosure (CVE-2026-59739) caused by a missing ACL check during SetWatches reconnect replay. An attacker can register exists-watches on non-existent paths and reconnect after those paths are created, revealing the existence of ACL-restricted paths. The issue is fixed in patched releases.

CVE-2026-79993: Apache ZooKeeper: Missing ACL check on deleteContainer opcode allows unauthorized deletion of any empty persistent/container znode

Critical ZooKeeper flaw lets any authenticated client delete arbitrary empty persistent or container znodes by bypassing ACL checks.

CVE-2026-79993 (critical severity) affects Apache ZooKeeper 3.9.0-3.9.5 and 3.8.0-3.8.6. The deleteContainer opcode (0x14/20) is processed without verifying the caller's ACL permissions, allowing any authenticated client to delete specific empty znodes in the data tree regardless of ACL restrictions on the znode or its parent. This can corrupt coordination state for dependent distributed systems like Kafka, HBase, or Solr clusters relying on ZooKeeper.