Executive brief
Wazuh is an open-source security platform used for threat detection and incident response across corporate networks. A vulnerability in its cluster management system allows an attacker who has access to the cluster's shared key to take control of the master management node. This could result in the creation of unauthorized administrative users, the modification of security configurations, or the deletion of critical security data, effectively compromising the entire monitoring infrastructure.
Technical details
The vulnerability consists of two chained issues within the Wazuh Cluster Distributed API (DAPI). First, the `as_wazuh_object()` function in `framework/wazuh/core/cluster/common.py` performs unsafe deserialization of JSON objects, allowing the resolution of arbitrary Python callables within the 'wazuh' or 'api' packages. Second, the DAPI implementation in `framework/wazuh/core/cluster/dapi/dapi.py` allows clients to supply their own `rbac_permissions` and `rbac_mode`. By providing a 'black' (deny-list) RBAC mode with no restrictions, an attacker can bypass authorization checks for functions protected by the `@expose_resources` decorator. An attacker with access to the shared cluster key can exploit these issues to perform arbitrary file writes, create new API users, or tamper with `security.yaml` on the master node. The issue is fixed in version 4.14.5.
Affected products
- Wazuh Wazuh >= 4.0.0, < 4.14.5
Timeline
- 2026-07-16: advisory: GitHub advisory GHSA-w2jj-pfq9-mh9p published
- 2026-07-20: disclosed: CVE-2026-28220 published to NVD
- 2026-07-20: patched: Fix released in version 4.14.5