Description
While an Apache Kafka cluster is being migrated from ZooKeeper mode to KRaft mode, in some cases ACLs will not be correctly enforced.
Two preconditions are needed to trigger the bug:
1. The administrator decides to remove an ACL
2. The resource associated with the removed ACL continues to have two or more other ACLs associated with it after the removal.
When those two preconditions are met, Kafka will treat the resource as if it had only one ACL associated with it after the removal, rather than the two or more that would be correct.
The incorrect condition is cleared by removing all brokers in ZK mode, or by adding a new ACL to the affected resource. Once the migration is completed, there is no metadata loss (the ACLs all remain).
The full impact depends on the ACLs in use. If only ALLOW ACLs were configured during the migration, the impact would be limited to availability impact. if DENY ACLs were configured, the impact could include confidentiality and integrity impact depending on the ACLs configured, as the DENY ACLs might be ignored due to this vulnerability during the migration period.
Understanding This Vulnerability
This Common Vulnerabilities and Exposures (CVE) entry provides detailed information about a security vulnerability that has been publicly disclosed. CVEs are standardized identifiers assigned by MITRE Corporation to track and catalog security vulnerabilities across software and hardware products.
The severity rating (HIGH) indicates the potential impact of this vulnerability based on the CVSS (Common Vulnerability Scoring System) framework. Higher severity ratings typically indicate vulnerabilities that could lead to more significant security breaches if exploited. Security teams should prioritize remediation efforts based on severity, exploit availability, and the EPSS (Exploit Prediction Scoring System) score, which predicts the likelihood of exploitation in the wild.
If this vulnerability affects products or systems in your infrastructure, we recommend reviewing the affected products section, checking for available patches or updates from vendors, and implementing recommended workarounds or solutions until a permanent fix is available. Organizations should also monitor security advisories and threat intelligence feeds for updates about active exploitation of this vulnerability.