CVE-2023-44981 Apache ZooKeeper: Authorization bypass in SASL Quorum Peer Authentication
Attackers can bypass SASL authentication to join the cluster and modify data if quorum peer authentication is enabled.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-44981?
CVE-2023-44981 is a critical authentication bypass vulnerability in Debian Debian Linux, published on 11 Oct 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-639
Which versions are affected by CVE-2023-44981?
7 open source packages ship an affected version, including org.apache.zookeeper:zookeeper and zookeeper. It affects 2 products.
| Package | Affected | Fixed in |
|---|---|---|
org.apache.zookeeper:zookeeper Maven | All versions | 3.7.2 |
org.apache.zookeeper:zookeeper Maven | All versions | 3.7.2 |
org.apache.zookeeper:zookeeper Maven | From 3.8.0 | 3.8.3 |
org.apache.zookeeper:zookeeper Maven | From 3.8.0 | 3.8.3 |
org.apache.zookeeper:zookeeper Maven | From 3.9.0 | 3.9.1 |
org.apache.zookeeper:zookeeper Maven | From 3.9.0 | 3.9.1 |
1 more packages
zookeeper Bitnami | All versions to 3.9.0 | 3.7.2, 3.8.3 |
Products include Apache Zookeeper, Debian Debian Linux.
How do I fix CVE-2023-44981?
Upgrade org.apache.zookeeper:zookeeper to a fixed version for your release line: 3.7.2, 3.8.3 or 3.9.1.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2023-44981 being exploited?
There is no known exploitation of CVE-2023-44981 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
- CVE-2024-51504 Apache ZooKeeper: Authentication bypass with IP-based authentication in Admin Server
- CVE-2016-5017 Memory corruption in n/a
- CVE-2026-59739 Apache ZooKeeper: Information disclosure via SetWatches reconnect replay
- CVE-2026-59969 Apache ZooKeeper: Improper validation of certificate with host mismatch in FIPS mode
- CVE-2026-79993 Missing authorization in Apache ZooKeeper
Sources
Also known as BIT-zookeeper-2023-44981, CLEANSTART-2026-QV72304, DEBIAN-CVE-2023-44981, DLA-3624-1, DSA-5544-1, GHSA-7286-pgfv-vxvh and 11 more.