# CVE-2011-2005: Microsoft Ancillary Function Driver (afd.sys) Improper Input Validation Vulnerability

Source: https://junglewise.ai/threats/cve-2011-2005-microsoft-ancillary-function-driver-afd-sys-improper-input  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2022-03-28. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2011-2005 · Severity: critical · CVSS 7.8 · Exploited in the wild · Published 2022-03-28

The Ancillary Function Driver (afd.sys) in Microsoft Windows fails to properly validate user-mode input passed to kernel mode. This flaw allows a local attacker to gain elevated privileges by executing a specially crafted application.

Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2011-2005 exploited in the wild?** Yes. CVE-2011-2005 is known to be exploited in the wild, first recorded on 28 March 2022. Treat it as urgent.

**How severe is CVE-2011-2005?** Critical severity, with a CVSS score of 7.8, published 28 March 2022.

**Which products and versions are affected?** Microsoft Windows XP SP2, SP3; Microsoft Windows Server 2003 SP2.

**Is there a fix for CVE-2011-2005?** A patch was published on 2011-10-11: Microsoft released security bulletin MS11-080 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2011-2005 attacked?** It is attacked with local access, in an operating system.

**Am I affected by CVE-2011-2005?** Check whether you run Microsoft Ancillary Function Driver (AFD.sys). Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Microsoft Windows XP SP2, SP3
- Microsoft Windows Server 2003 SP2

## Timeline

- 2011-10-11: disclosed: NVD Published Date
- 2011-10-11: patched: Microsoft released security bulletin MS11-080
- 2022-03-28: kev added: Added to CISA Known Exploited Vulnerabilities Catalog