# CVE-2026-94383: MISP Blocklist Workflow Module: Arbitrary Script Execution via Unrestricted File Extension

> Site administrators can upload arbitrary script files via the blocklist workflow, leading to remote code execution if the web server executes scripts from the export directory.

- **Severity:** High 8.6 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 21 Sep 2026
- **Updated:** 21 Sep 2026
- **Also known as:** GHSA-8q25-97q9-g9wh

## What is CVE-2026-94383?

CVE-2026-94383 is a high-severity vulnerability in MISP, published on 21 Sep 2026. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

The MISP blocklist workflow module accepted a user-supplied blocklist filename parameter without validating the file extension. The only sanitization applied was basename() to strip path components and a check for empty or dot values. A site administrator could specify a filename with an arbitrary extension that would be placed in the MISP export directory. If the underlying web server is configured to interpret and execute scripts from that directory, the resulting file could be invoked, leading to arbitrary code execution in the context of the web server process.

The vulnerability requires the attacker to hold site-administrator privileges within MISP, as the blocklist workflow module is restricted to that role. No additional user interaction is required beyond triggering the workflow action with a crafted filename parameter. The impact is full compromise of the MISP server's confidentiality, integrity, and availability, as arbitrary script execution grants the attacker the same privileges as the web server user.

Version affected: <2.5.47

Weakness: CWE-434 (Unrestricted Upload of File with Dangerous Type), CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2026-94383?


## How do I fix CVE-2026-94383?

No fix has been published for CVE-2026-94383 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-94383 being exploited?

There is no known exploitation of CVE-2026-94383 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-94383 and fix it if it is affected.

What it is: CVE-2026-94383 is a high-severity vulnerability in MISP, published on 21 Sep 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-94383 in the wild and no public exploit code.

Affected product: MISP. 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-2026-94383/ (Markdown: https://insights.sbomify.com/CVE-2026-94383/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-94383
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-94383
- OSV: https://osv.dev/vulnerability/CVE-2026-94383

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-94383/
Summaries are generated and may contain mistakes; the official description above is the record.