# CVE-2023-39469: PaperCut NG External User Lookup Code Injection Remote Code Execution Vulnerability

> Authenticated attackers can execute arbitrary code with SYSTEM privileges via improper validation in the External User Lookup feature.

- **Severity:** High 7.2 (`CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 3 May 2024
- **Updated:** 2 Aug 2024
- **Also known as:** GHSA-h7m6-3v2j-jm33

## What is CVE-2023-39469?

CVE-2023-39469 is a high-severity code injection vulnerability in PaperCut NG, published on 3 May 2024. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

PaperCut NG External User Lookup Code Injection Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of PaperCut NG. Authentication is required to exploit this vulnerability.

The specific flaw exists within the External User Lookup functionality. The issue results from the lack of proper validation of a user-supplied string before using it to execute Java code. An attacker can leverage this vulnerability to execute code in the context of SYSTEM. Was ZDI-CAN-21013.

Weakness: CWE-94 (Improper Control of Generation of Code)

## Which versions are affected by CVE-2023-39469?

It affects 2 products.


Products: Papercut Papercut Mf, Papercut Papercut Ng.

## How do I fix CVE-2023-39469?

No fix has been published for CVE-2023-39469 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-39469 being exploited?

There is no known exploitation of CVE-2023-39469 in the wild and no public exploit code.

## Other vulnerabilities in PaperCut NG

- [CVE-2023-27350](https://insights.sbomify.com/CVE-2023-27350/): PaperCut MF/NG Improper Access Control (critical 9.8, exploited in the wild)
- [CVE-2026-82078](https://insights.sbomify.com/CVE-2026-82078/): PaperCut NG/MF Unsafe Reflection (critical 9.4, exploited in the wild)
- [CVE-2026-81578](https://insights.sbomify.com/CVE-2026-81578/): PaperCut NG/MF Missing Authentication for Critical Function (high 8.8, exploited in the wild)
- [CVE-2023-2533](https://insights.sbomify.com/CVE-2023-2533/): PaperCut NG/MF Cross-Site Request Forgery (CSRF) (high 8.4, exploited in the wild)
- [CVE-2023-27351](https://insights.sbomify.com/CVE-2023-27351/): PaperCut NG/MF Improper Authentication (high 8.2, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-39469 and fix it if it is affected.

What it is: CVE-2023-39469 is a high-severity code injection vulnerability in PaperCut NG, published on 3 May 2024. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2023-39469 in the wild and no public exploit code.

Affected product: PaperCut NG. 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-2023-39469/ (Markdown: https://insights.sbomify.com/CVE-2023-39469/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-39469
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-39469
- OSV: https://osv.dev/vulnerability/CVE-2023-39469

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-39469/
Summaries are generated and may contain mistakes; the official description above is the record.