---
title: "CVE-2023-44981: Authorization Bypass Through User-Controlled Key vulnerability in Apache ZooKeeper"
url: https://erroneo.us/security/cve/CVE-2023-44981/
description: "CVE-2023-44981 (org.apache.zookeeper:zookeeper (Maven)): Authorization Bypass Through User-Controlled Key vulnerability in Apache ZooKeeper. If SASL Quorum…"
type: vulnerability-record
section: "Security Digest"
date_published: 2023-10-11
date_modified: 2025-04-23
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2023-44981"
kev: false
cvss: 9.1
epss: 0.02221
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2023-44981: Authorization Bypass Through User-Controlled Key vulnerability in Apache ZooKeeper

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 2.2% , percentile 83: FIRST’s model estimates a 2.2% chance of exploitation activity in the next 30 days, higher than 83% of all scored CVEs (elevated). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes org.apache.zookeeper:zookeeper (Maven) < 3.7.2, fixed in 3.7.2 ; org.apache.zookeeper:zookeeper (Maven) >= 3.8.0, < 3.8.3, fixed in 3.8.3 ; org.apache.zookeeper:zookeeper (Maven) >= 3.9.0, < 3.9.1, fixed in 3.9.1 . Check your lockfile, including transitive dependencies.

## What it is

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.

## Affected packages

- Maven `org.apache.zookeeper:zookeeper` < 3.7.2 → fixed: 3.7.2
- Maven `org.apache.zookeeper:zookeeper` >= 3.8.0, < 3.8.3 → fixed: 3.8.3
- Maven `org.apache.zookeeper:zookeeper` >= 3.9.0, < 3.9.1 → fixed: 3.9.1

## Affected products (CVE record)

- Apache Software Foundation Apache ZooKeeper: 3.9.0 < 3.9.1, 3.8.0 <= 3.8.2, 3.7.0 <= 3.7.1, < 3.7.0

## Severity

- CISA-ADP CVSS 3.1: 9.1 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N`
- GitHub CVSS 3.1: 9.1 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 2.22% probability of exploitation activity in the next 30 days; percentile 83.

## Sources

- [lists.apache.org](https://lists.apache.org/thread/wf0yrk84dg1942z1o74kd8nycg6pgm5b)
- [GitHub Advisory GHSA-7286-pgfv-vxvh](https://github.com/advisories/GHSA-7286-pgfv-vxvh)
- [CVE.org record CVE-2023-44981](https://www.cve.org/CVERecord?id=CVE-2023-44981)
- [NVD entry CVE-2023-44981](https://nvd.nist.gov/vuln/detail/CVE-2023-44981)
- [openwall.com](http://www.openwall.com/lists/oss-security/2023/10/11/4)
- [lists.debian.org](https://lists.debian.org/debian-lts-announce/2023/10/msg00029.html)
- [debian.org](https://www.debian.org/security/2023/dsa-5544)
- [security.netapp.com](https://security.netapp.com/advisory/ntap-20240621-0007/)

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Source page: https://erroneo.us/security/cve/CVE-2023-44981/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt