Resource exhaustion in Wazuh

CVE-2026-25771

Wazuh is a free and open source platform used for threat prevention, detection, and response. Starting in version 4.3.0 and prior to version 4.14.3, a Denial of Service (DoS) vulnerability exists in the Wazuh API authentication middleware (`middlewares.py`). The application uses an asynchronous event loop (Starlette/Asyncio) to call a synchronous function (`generate_keypair`) that performs blocking disk I/O on every request containing a Bearer token. An unauthenticated remote attacker can exploit this by flooding the API with requests containing invalid Bearer tokens. This forces the single-threaded event loop to pause for file read operations repeatedly, starving the application of CPU resources and potentially preventing it from accepting or processing legitimate connections. Version 4.14.3 fixes the issue.

Vulnerability class: DoS (Denial of Service)

EPSS: 0.005 (37.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

Affected products

  • Wazuh — versions >= 4.3.0, < 4.14.3

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-25771?
CVE-2026-25771 is a medium-severity vulnerability in Wazuh, classified under Uncontrolled Resource Consumption. CVSS score: 5.3/10. Published 2026-03-17.
How severe is CVE-2026-25771?
Medium severity. CVSS v3 base score is 5.3 out of 10.