Improper Output Neutralization for Logs Affecting org.apache.zookeeper:zookeeper package, versions [3.8.0,3.8.7)[3.9.0,3.9.6)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-JAVA-ORGAPACHEZOOKEEPER-20159004
- published27 Sept 2026
- disclosed16 Sept 2026
- creditYoulong Chen Institute of Computing Technology
Introduced: 16 Sep 2026
NewCVE-2026-84501 (opens in a new tab)How to fix?
Upgrade org.apache.zookeeper:zookeeper to version 3.8.7, 3.9.6 or higher.
Overview
org.apache.zookeeper:zookeeper is a centralized service for maintaining configuration information, naming, providing distributed synchronization, and providing group services.
Affected versions of this package are vulnerable to Improper Output Neutralization for Logs via the handleAuthentication. An attacker can inject arbitrary log entries by sending a crafted authentication request containing newline characters, causing unsanitized input to be written to the operational log. This allows the attacker to forge log entries that are visually indistinguishable from legitimate ones, potentially misleading administrators or obscuring malicious activity.