Asterisk Project Security Advisory - AST-2013-001

          Product         Asterisk                                            
          Summary         Buffer Overflow Exploit Through SIP SDP Header      
     Nature of Advisory   Exploitable Stack Buffer Overflow                   
       Susceptibility     Remote Unauthenticated Sessions                     
          Severity        Major                                               
       Exploits Known     No                                                  
        Reported On       6 January, 2013                                     
        Reported By       Ulf Ha:rnhammar                                     
         Posted On        27 March, 2013                                      
      Last Updated On     March 27, 2013                                      
      Advisory Contact    Jonathan Rose <jrose AT digium DOT com>             
          CVE Name        CVE-2013-2685                                       

    Description  The format attribute resource for h264 video performs an     
                 unsafe read against a media attribute when parsing the SDP.  
                 The vulnerable parameter can be received as strings of an    
                 arbitrary length and Asterisk attempts to read them into     
                 limited buffer spaces without applying a limit to the        
                 number of characters read. If a message is formed            
                 improperly, this could lead to an attacker being able to     
                 execute arbitrary code remotely.                             

    Resolution  Attempts to read string data into the buffers noted are now   
                explicitly limited by the size of the buffers.                

                               Affected Versions
                Product              Release Series  
         Asterisk Open Source             11.x       All Versions             

                                  Corrected In  
                     Product                              Release             
               Asterisk Open Source                        11.2.2             

                                    Patches                        
                               SVN URL                              Revision  
   Http://downloads.asterisk.org/pub/security/AST-2013-001-11.diff Asterisk   
                                                                   11         

       Links     https://issues.asterisk.org/jira/browse/ASTERISK-20901       

    Asterisk Project Security Advisories are posted at                        
    http://www.asterisk.org/security                                          
                                                                              
    This document may be superseded by later versions; if so, the latest      
    version will be posted at                                                 
    http://downloads.digium.com/pub/security/AST-2013-001.pdf and             
    http://downloads.digium.com/pub/security/AST-2013-001.html                

                                Revision History
            Date                  Editor               Revisions Made         
    February 11, 2013      Jonathan Rose         Initial Draft                
    March 27, 2013         Matt Jordan           CVE Added                    

               Asterisk Project Security Advisory - AST-2013-001
              Copyright (c) 2013 Digium, Inc. All Rights Reserved.
  Permission is hereby granted to distribute and publish this advisory in its
                           original, unaltered form.