# CVE-2026-74040: Wazuh 3.9.0 before 4.14.8 Arbitrary File Overwrite RCE via process_files_from_worker

> A cluster worker can overwrite master configuration files to achieve root remote code execution on the manager and all agents.

- **Severity:** Critical 9.4 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 13 Oct 2026
- **Updated:** 26 Oct 2026
- **Also known as:** GHSA-88p6-7cm8-xwj8

## What is CVE-2026-74040?

CVE-2026-74040 is a critical path traversal vulnerability in wazuh-manager, published on 13 Oct 2026. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

Wazuh versions from 3.9.0 before 4.14.8 contain an arbitrary file overwrite vulnerability in MasterHandler.process_files_from_worker allowing a cluster worker to overwrite protected master files. Attackers controlling a worker can use a trailing-slash basename bypass and missing extra_valid enforcement to overwrite ossec.conf and agent.conf, achieving root remote code execution across the manager and every agent.

Weakness: CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2026-74040?


## How do I fix CVE-2026-74040?

No fix has been published for CVE-2026-74040 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-74040 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-74040 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-74040 and fix it if it is affected.

What it is: CVE-2026-74040 is a critical path traversal vulnerability in wazuh-manager, published on 13 Oct 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-74040 exists.

Affected product: wazuh-manager. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-74040/ (Markdown: https://insights.sbomify.com/CVE-2026-74040/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-74040
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-74040
- OSV: https://osv.dev/vulnerability/CVE-2026-74040

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-74040/
Summaries are generated and may contain mistakes; the official description above is the record.