CVE-2026-71540 — HIGH (7.5)

Vulnerability Description

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.

CVSS Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

NONE

Integrity

NONE

Availability

HIGH

Related Weaknesses (CWE)

CWE-770

References

FAQ

What is CVE-2026-71540?

CVE-2026-71540 is a vulnerability with a CVSS score of 7.5 (HIGH). 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...

How severe is CVE-2026-71540?

CVE-2026-71540 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-71540?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.