Wazuh · Wazuh Server · Wazuh Server Deserialization of Untrusted Data Vulnerability
Verdict
Patch soon · actively exploited, not reachable unauthenticated from the internet, and in the top 1% of CVEs by near-term exploitation probability
Added to CISA KEV 2025-06-10 · exploited in the wild for 474 days
CVSS 9.9 CRITICAL. The score is a summary; these three components are the part that decides whether something scanning the internet can use it.
| Attack vector | networkreachable over the network, with no local access needed |
|---|---|
| Privileges required | lowneeds some credentials, so a fully anonymous attacker cannot reach it directly |
| User interaction | nonecan be triggered with nobody interacting with the page or request |
| Base vector | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:H |
| Weakness | CWE-502 |
This describes the vulnerability. It says nothing about whether your systems run it.
EPSS puts the probability of exploitation in the next 30 days at 0.9384, which places it in the top 1% of all tracked CVEs. The percentile is the more useful half: 0.18 in absolute terms sounds low until you know most of the internet-facing software in the world scores under that.
| EPSS probability | 0.9384 |
|---|---|
| Percentile | 0.998 — top 1% |
| Added to KEV | 2025-06-10 |
|---|---|
| Days exploited | 474 |
| Federal remediation due | not set |
| Ransomware use | no known ransomware campaign use |
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Wazuh is a free and open source platform used for threat prevention, detection, and response. Starting in version 4.4.0 and prior to version 4.9.1, an unsafe deserialization vulnerability allows for remote code execution on Wazuh servers. DistributedAPI parameters are a serialized as JSON and deserialized using `as_wazuh_object` (in `framework/wazuh/core/cluster/common.py`). If an attacker manages to inject an unsanitized dictionary in DAPI request/response, they can forge an unhandled exception (`__unhandled_exc__`) to evaluate arbitrary python code. The vulnerability can be triggered by anybody with API access (compromised dashboard or Wazuh servers in the cluster) or, in certain configurations, even by a compromised agent. Version 4.9.1 contains a fix.