CVE-2026-28220: wazuh Deserialization of Untrusted Data

Vulnerability summary

CVE-2026-28220 is a critical (CVSS 9.1) Deserialization of Untrusted Data vulnerability in wazuh. EPSS estimates a 0.66% chance of exploitation in the next 30 days, higher than 50.7% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 20-07-2026
   PublishedVulnerability first disclosed.
2. 20-07-2026
   Last modifiedVulnerability information updated.

Description

Wazuh is a free and open source platform used for threat prevention, detection, and response. Prior to version 4.14.5, issues in the Cluster Distributed API (DAPI) handling allow a cluster peer, or any actor able to authenticate to the cluster channel using the shared cluster key, to make the master node deserialize an attacker-controlled callable and execute it under an attacker-controlled RBAC context. The cluster code in `framework/wazuh/core/cluster/common.py` deserializes JSON with `as_wazuh_object()`, which resolves any callable whose top-level package is wazuh or api (an overly broad allowlist controlled only by `ALLOWED_CALLABLES_PACKAGES`), and DAPI requests handled in framework/wazuh/core/cluster/dapi/dapi.py accept a client-supplied rbac_permissions value that `run_local()` applies as the global RBAC context, so supplying an rbac_mode of black causes authorization checks for expose_resources-protected functions to pass without any legitimate permission assignment. Combined, these allow privileged administrative actions on the master node such as arbitrary file writes under WAZUH_PATH, creation of new API users, and tampering with security.yaml, and can be chained into full manager compromise. This issue has been fixed in version 4.14.5.

• CWE-502Deserialization of Untrusted DataThe product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.