Buffer overflow in Wazuh

CVE-2026-45798

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.

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.009 (58.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 59th percentile — 58.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-45798: held from 0.005 to 0.009.

EPSS over last 30 days · oldest: 0.005 · newest: 0.009 · change: +0.004

Affected products

  • Wazuh — versions 5.0.0, >= 5.0.0-beta1, < 5.0.0-beta2, >= 4.5.0, < 4.14.6

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-45798?
CVE-2026-45798 is a high-severity vulnerability in Wazuh, classified under Stack-based Buffer Overflow. CVSS score: 7.5/10. Published 2026-08-19.
How severe is CVE-2026-45798?
High severity. CVSS v3 base score is 7.5 out of 10.