Resource exhaustion in Wazuh
CVE-2026-44253
Wazuh is a free and open source platform used for threat prevention, detection, and response. From 3.9.0 until 4.14.5 and 5.0.0-beta2, the Wazuh cluster protocol in framework/wazuh/core/cluster/common.py allows an authenticated cluster node to exhaust memory on the master. The receive_str() method accepts an attacker-controlled total for InBuffer without a maximum, so a new_str command can request a multi-gigabyte bytearray and repeated requests accumulate in in_str. The divided-message path also retains flag_divided fragments under unique counters in div_msg_box without a count, aggregate-size, or expiration limit. Exploitation can disrupt agent connectivity and alert processing across the monitored environment. This issue is fixed in versions 4.14.5 and 5.0.0-beta2.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.9 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.006 (47.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 47th percentile — 47.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.006 · change: +0.002
Affected products
- Wazuh — versions 5.0.0, >= 5.0.0-beta1, < 5.0.0-beta2, >= 3.9.0, < 4.14.5
Weakness classification (CWE)
References
- github.com/wazuh/wazuh/commit/d29c5c89a0e16477545ca27f4e06229021e3183c (Patch)
- github.com/wazuh/wazuh/pull/35173 (Patch, Issue Tracking)
- github.com/wazuh/wazuh/releases/tag/v4.14.5 (Patch, Release Notes)
- github.com/wazuh/wazuh/security/advisories/GHSA-h5r8-gvhv-cmp2 (Exploit, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-44253?
- CVE-2026-44253 is a medium-severity vulnerability in Wazuh, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 4.9/10. Published 2026-08-19.
- How severe is CVE-2026-44253?
- Medium severity. CVSS v3 base score is 4.9 out of 10.