CVE-2026-45798: Wazuh: Pre-auth stack-buffer-overflow in compare_wazuh_versions reachable from wazuh-authd (TCP/1515) via crafted enrollment V: field

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.9% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-08-19 · updated 2026-10-26
Weakness: CWE-121

Description

Wazuh is a free and open source platform used for threat prevention, detection, and response. From 4.5.0 until 4.14.6 and 5.0.0-beta2, compare_wazuh_versions() in src/shared/version_op.c copies the attacker-controlled enrollment V: field into a 10-byte stack buffer with strncpy() but does not explicitly terminate the buffer. The function is reachable before authentication through wazuh-authd on TCP port 1515 when anonymous TLS enrollment is enabled. A version string of at least nine non-null bytes can cause strchr() and strtok() to read beyond ver2 and can make strtok() write a null byte into adjacent stack memory, allowing a remote denial of service. This issue is fixed in versions 4.14.6 and 5.0.0-beta2.

Affected products

wazuh: from 4.5.0 before 4.14.6; 5.0.0-beta1 — fixed in 4.14.6

How to fix

Upgrade to a fixed version: wazuh 4.14.6. Check the vendor advisory for mitigations.

References

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