CVE-2026-25771 json
Wazuh Vulnerable to Denial of Service via Synchronous I/O Blocking in Asynchronous Authentication Middleware
published 2026-03-17 7 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-12620
- cvss
- 5.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 42%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- wazuh wazuh 4.14.3
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 7 mo ago
Exploit prediction
0.50% chance of exploitation in the next 30 days, higher than 42% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/wazuh/wazuh/security/advisories/GHSA-33w3-p5hm-jw7g referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected products
- wazuh wazuh
Classification
- Weakness
-
- CWE-400 Uncontrolled Resource Consumption
References
-
github.com
/wazuh/wazuh/security/advisories/GHSA-33w3-p5hm-jw7g
exploit, mitigation, vendor-advisory
Sources
- CVE List CVE-2026-25771
- NVD CVE-2026-25771
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