CVE-2023-44981 — zookeeper
CRITICALCVE-2023-44981 is a critical-severity (CVSS 9.1) CWE-639 vulnerability in org.apache.zookeeper:zookeeper. A fix is available for org.apache.zookeeper:zookeeper — see the affected versions and patch details below.
Apache ZooKeeper: Authorization bypass in SASL Quorum Peer Authentication
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-44981.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2023-44981 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 384,189 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
org.apache.zookeeper:zookeeper☕org.apache.zookeeper:zookeeper☕org.apache.zookeeper:zookeeperReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.apache.zookeeper:zookeeper | all versions | 3.7.2org.apache.zookeeper:zookeeper:3.7.2 |
| ☕Maven | org.apache.zookeeper:zookeeper | ≥ 3.8.0&&< 3.8.3 | 3.8.3org.apache.zookeeper:zookeeper:3.8.3 |
| ☕Maven | org.apache.zookeeper:zookeeper | ≥ 3.9.0&&< 3.9.1 | 3.9.1org.apache.zookeeper:zookeeper:3.9.1 |
Affected Products
zookeeperapachedebian linuxdebianDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.zookeeper:zookeeper, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.apache.zookeeper:zookeeper to 3.7.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-44981 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
Red Hat AMQ 7 Broker and Red Hat AMQ Streams 2 use Zookeeper but do not use or enable the vulnerable functionality, Peer Authentication. They are affected at Moderate Impact by this flaw. Red Hat Fuse 7 uses Zookeeper but does not use any of its server capabilities and as such is not vulnerable, and so is affected at…
According to Apache's document: Ensure the ensemble election/quorum communication is protected by a firewall as this will mitigate the issue.Source: Red Hat security advisory for CVE-2023-44981 (CC BY 4.0)
| Product | Fixed in | Advisory |
|---|---|---|
| AMQ Broker 7.10.6 | see advisory | RHSA-2024:0903 |
| Red Hat AMQ Broker 7 | see advisory | RHSA-2024:2945 |
| Red Hat AMQ Broker 7.11.6 | zookeeper | RHSA-2024:0705 |
| Red Hat AMQ Streams 2.6.0 | zookeeper | RHSA-2023:7678 |
Frequently Asked Questions
Is CVE-2023-44981 in your dependencies?
Find it across Maven, including transitive dependencies.