What is CVE-2026-71540?

CVE-2026-71540 is a high-severity vulnerability in Wazuh, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 7.5/10. Published 2026-09-24.

How severe is CVE-2026-71540?

High severity. CVSS v3 base score is 7.5 out of 10.

Resource exhaustion in Wazuh

CVE-2026-71540

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.

Published 2026-09-24.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Wazuh — versions >= 3.9.0, < 4.14.7

Weakness classification (CWE)

CWE-770 — Allocation of Resources Without Limits or Throttling

References

Frequently asked questions

What is CVE-2026-71540?: CVE-2026-71540 is a high-severity vulnerability in Wazuh, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 7.5/10. Published 2026-09-24.
How severe is CVE-2026-71540?: High severity. CVSS v3 base score is 7.5 out of 10.