Auth bypass in Apache Zookeeper
CVE-2023-44981
Authorization Bypass Through User-Controlled Key vulnerability in Apache ZooKeeper. If SASL Quorum Peer authentication is enabled in ZooKeeper (quorum.auth.enableSasl=true), the authorization is done by verifying that the instance part in SASL authentication ID is listed in zoo.cfg server list. The instance part in SASL auth ID is optional and if it's missing, like 'eve@EXAMPLE.COM', the authorization check will be skipped. As a result an arbitrary endpoint could join the cluster and begin propagating counterfeit changes to the leader, essentially giving it complete read-write access to the data tree. Quorum Peer authentication is not enabled by default. Users are recommended to upgrade to version 3.9.1, 3.8.3, 3.7.2, which fixes the issue. Alternately ensure the ensemble election/quorum communication is protected by a firewall as this will mitigate the issue. See the documentation for more details on correct cluster administration.
Vulnerability class: IDOR (Insecure Direct Object Reference)
EPSS: 0.017 (76.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.
Affected products
- Apache Zookeeper — versions 3.9.0
- Apache Software Foundation Zookeeper — versions 3.9.0, 3.8.0, 3.7.0
- Debian Debian_linux — versions 10.0, 11.0, 12.0
Weakness classification (CWE)
References
- security@apache.org (vendor-advisory, Issue Tracking, Vendor Advisory)
- security@apache.org (Mailing List, Third Party Advisory)
- security@apache.org (Mailing List)
- security@apache.org (Mailing List, Third Party Advisory)
- security@apache.org
Frequently asked questions
- What is CVE-2023-44981?
- CVE-2023-44981 is a critical-severity vulnerability in Apache Zookeeper, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 9.1/10. Published 2023-10-11.
- How severe is CVE-2023-44981?
- Critical severity. CVSS v3 base score is 9.1 out of 10.