CVE-2026-71540CWE-770denial-of-service

CVE-2026-71540

High · published September 24, 2026

CVSS v3.1
7.5
EPSS
0%
Percentile
27.4
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00350 · 27.4th percentile
Weakness
CWE-770 · Allocation of Resources Without Limits or Throttling
Published
2026-09-24T22:18Z
References (5)
EPSS history
Timeline
  • 26 SEP 03:26Z
    EPSS moved — → 0%
    epss
  • 24 SEP 17:49Z
    Wazuh Manager cluster header parsing allows pre-authentication memory exhaustion
    cvelistv5