Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1336 CNY

100%
Buy Us a Coffee

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

Quick assessment

Affected
Apache Software Foundation Apache ZooKeeper
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

When audit logging is enabled (zookeeper.audit.enable=true), an unauthenticated attacker can inject arbitrary fields into Apache ZooKeeper's audit log by sending a digest authentication request with tab characters (\t) embedded in the username. Because the aud

AI Predicted 5.3 Difficulty: Easy
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-84439

Vulnerability Information

Shenlong is analyzing...

Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Apache ZooKeeper: Audit log injection via unsanitized output from multiple sources
Source: CVE Program / CVE List V5
Vulnerability Description
When audit logging is enabled (zookeeper.audit.enable=true), an unauthenticated attacker can inject arbitrary fields into Apache ZooKeeper's audit log by sending a digest authentication request with tab characters (\t) embedded in the username. Because the audit log uses tab-separated key=value format, the injected tabs are parsed as legitimate field separators, allowing the attacker to spoof audit results (e.g., injecting result=success), forge operation types, and corrupt forensic evidence. A log injection vulnerability in Apache ZooKeeper allows a client that can call setACL to inject forged key-value fields into zookeeper_audit.log. When audit logging is enabled, the server serializes attacker-controlled digest ACL ids into the acl= audit field without escaping tab characters. Because audit events are emitted as tab-separated key=value records, a crafted ACL id can make one successful setAcl event appear to contain forged fields such as operation=delete and znode=/forged. This undermines the integrity of downstream audit parsing, alerting, and incident response. This issue affects Apache ZooKeeper: from 3.9.0 through 3.9.5, from 3.8.0 through 3.8.6. Users are recommended to upgrade to version 3.9.6 or 3.8.7, which fixes the issue.
Source: CVE Program / CVE List V5
CVSS Information
N/A
Source: CVE Program / CVE List V5
Vulnerability Type
日志输出的转义处理不恰当
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
Apache Software Foundation Apache ZooKeeper 3.9.0 ~ 3.9.5 -

II. Public POCs for CVE-2026-84439

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-84439

请登录查看更多情报信息。

Mailing List Discussions for CVE-2026-84439 (1)

Same Patch Batch · Apache Software Foundation · 2026-09-16 · 13 CVEs total

CVE-2026-84501 Apache ZooKeeper: Operational log forgery via newline injection in EnsembleAuthenticationP
CVE-2026-79993 Apache ZooKeeper: Missing ACL check on deleteContainer opcode allows unauthorized deletion
CVE-2026-59969 Apache ZooKeeper: Improper validation of certificate with host mismatch in FIPS mode
CVE-2026-59739 Apache ZooKeeper: Information disclosure via SetWatches reconnect replay
CVE-2026-86466 Apache Airflow FAB provider: FAB Authentik provider: id_token issuer/audience not validate
CVE-2026-76187 Apache Airflow Keycloak provider: Any realm client's credentials mint an Airflow session J
CVE-2026-76186 Apache Airflow Keycloak provider: Keycloak token cookies not bound to Airflow session iden
CVE-2026-82310 Apache Airflow FAB provider: FAB auth manager: deactivated users retain and renew Core API
CVE-2026-86792 Apache Airflow Apache Kafka provider: Connection-editor remote code execution on the Sched
CVE-2026-86462 Apache Airflow FAB provider: FAB Admin password PATCH does not invalidate database-backed
CVE-2026-82311 Apache Airflow FAB provider: FAB password reset never invalidates sessions: string/int _us
CVE-2026-86465 Apache Airflow Akeyless provider: Akeyless secrets backend: team-scope guard bypass via us

IV. Related Vulnerabilities

Same product: Apache ZooKeeper
Same vendor: Apache Software Foundation
Same weakness: CWE-117

V. Comments for CVE-2026-84439

No comments yet

Leave a comment