---
id: CVE-2026-71540
title: >-
  Wazuh is an open-source security platform providing unified XDR and SIEM
  protection for endpoints and cloud workloads
summary: >-
  Wazuh is an open-source security platform providing unified XDR and SIEM
  protection for endpoints and cloud workloads. From 3.9.0 until 4.14.7,
  wazuh-clusterd in framework/wazuh/core/cluster/common.py allocates a payload
  buffer using the…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-770
vendor: wazuh
product: wazuh
affected:
  - 'wazuh >= 3.9.0, < 4.14.7'
published: '2026-09-24'
updated: '2026-09-30'
sourceUpdated: '2026-09-30T19:38:27.293'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-71540'
references:
  - url: >-
      https://github.com/wazuh/wazuh/commit/9a996bc23d28725f6c1f8f7808355d90e20d3382
    label: security-advisories@github.com
  - url: 'https://github.com/wazuh/wazuh/pull/37280'
    label: security-advisories@github.com
  - url: 'https://github.com/wazuh/wazuh/releases/tag/v4.14.7'
    label: security-advisories@github.com
  - url: 'https://github.com/wazuh/wazuh/security/advisories/GHSA-78wx-4r6w-w73f'
    label: security-advisories@github.com
  - url: 'https://github.com/wazuh/wazuh/security/advisories/GHSA-78wx-4r6w-w73f'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - exploit-available
epss: 0.00425
epssPercentile: 0.36604
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-28T15:01:49.339177Z'
ingestedAt: '2026-09-24T18:49:36.710Z'
---

## Overview

Wazuh is an open-source security platform providing unified XDR and SIEM protection for endpoints and cloud workloads. From 3.9.0 until 4.14.7, wazuh-clusterd in framework/wazuh/core/cluster/common.py allocates a payload buffer using the size declared in a 20-byte cluster protocol header before Fernet decryption validates the peer. An unauthenticated network peer can declare a payload of up to 256 MiB, stop sending after the header, and retain that allocation until the TCP connection closes. The cluster listener has no application-level per-source connection budget in affected versions, allowing concurrent sockets to multiply memory consumption and potentially terminate the cluster process, disrupt synchronization, and interrupt distributed API forwarding. This issue is fixed in version 4.14.7.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.