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 '[email protected]', 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.

CVE-2023-44981 has a CVSS score of 9.1 (Critical). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (3.7.2, 3.8.3, 3.9.1); upgrading removes the vulnerable code path.

Kodem intelligence

1. What is CVE-2023-44981? CVE-2023-44981 is a critical-severity security vulnerability in org.apache.zookeeper:zookeeper (maven), affecting versions < 3.7.2. It is fixed in 3.7.2, 3.8.3, 3.9.1.
2. How severe is CVE-2023-44981? CVE-2023-44981 has a CVSS score of 9.1 (Critical). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of org.apache.zookeeper:zookeeper are affected by CVE-2023-44981? org.apache.zookeeper:zookeeper (maven) versions < 3.7.2 is affected.
4. Is there a fix for CVE-2023-44981? Yes. CVE-2023-44981 is fixed in 3.7.2, 3.8.3, 3.9.1. Upgrade to this version or later.
5. Is CVE-2023-44981 exploitable, and should I be worried? Whether CVE-2023-44981 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2023-44981 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2023-44981?
   • Upgrade org.apache.zookeeper:zookeeper to 3.7.2 or later
   • Upgrade org.apache.zookeeper:zookeeper to 3.8.3 or later
   • Upgrade org.apache.zookeeper:zookeeper to 3.9.1 or later