High severity · published Mar 17, 2026
CVE-2026-25771
Wazuh Vulnerable to Denial of Service via Synchronous I/O Blocking in Asynchronous Authentication Middleware
7.5
CVSS
0.5%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 42% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WA
wazuh · wazuh
>= 4.3.0, < 4.14.3 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-25771
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-25771
Exploit
https://github.com/wazuh/wazuh/security/advisories/GHSA-33w3-p5hm-jw7g
More from wazuh
9.9
CVE-2025-24016
Remote code execution in Wazuh server
9.9
CVE-2026-30893
Wazuh cluster sync path traversal in decompress_files() enables arbitrary file write and code execution from authenticated cluster peer
9.8
CVE-2024-32038
Wazuh is a free and open source platform used for threat prevention, detection, and response
9.8
CVE-2021-44079
In the wazuh-slack active response script in Wazuh 4.2.x before 4.2.5, untrusted user agents are passed to a curl command line, potentially resulting in remote code execution
9.3
CVE-2026-67308
Wazuh GitHub Actions Shell Injection via Fork Pull Request
