1. Overview
nmap <= 5.21 is vulnerable to Windows DLL Hijacking Vulnerability. 

2. Vulnerability Description
nmap passes insufficiently qualified path for the dll "airpcap.dll" while opening a file using nmap

Timeline
27-08-2010 - Discovered Vulnerability
31-08-2010 - Disclosed at nmap-dev mailing list
04-09-2010 - Response and fix from developers
05-09-2010 - Disclosure


3. Exploitability
A file extension needs to be registered with nmap to exploit the vulnerability and a crafted file needs to be opened from a network share. Currently nmap is not registered with any filename so users are not at risk by default.

4. Versions Affected
nmap 5.21 and lower.

5. POC/Exploit
Done with Webdav hijack module of Metasploit.

6. Impact
Remote Code Execution in context of nmap process.

7. References
http://seclists.org/nmap-dev/2010/q3/632

8. Solution
Fixed in latest development release.