Gammarays has discovered a vulnerability in LS simple guestbook, which can be exploited by malicious people to compromise a vulnerable system.

Input passed to the "message" parameter in index.php is not properly sanitised before it is written to the posts.txt file, which is included by the index.php script. This can be exploited to execute arbitrary PHP code.

The vulnerability is confirmed in version 1. Other versions may also be affected.

Solution
Edit the source code to ensure that input is properly sanitised.

Provided and/or discovered by
Gammarays

Changelog
Further details available to Secunia VIM customers

Original Advisory
http://milw0rm.com/exploits/3735

Deep Links
Links available to Secunia VIM customers