[asterisk-dev] AST-2016-008: Crash on SDP offer or answer from endpoint using Opus

[Asterisk Security Team]

               Asterisk Project Security Advisory - AST-2016-008

         Product        Asterisk                                              
         Summary        Crash on SDP offer or answer from endpoint using      
                        Opus                                                  
    Nature of Advisory  Remote Crash                                          
      Susceptibility    Remote unauthenticated sessions                       
         Severity       Critical                                              
      Exploits Known    No                                                    
       Reported On      November 11, 2016                                     
       Reported By      jorgen                                                
        Posted On       
     Last Updated On    November 15, 2016                                     
     Advisory Contact   jcolp AT digium DOT com                               
         CVE Name       

    Description  If an SDP offer or answer is received with the Opus codec    
                 and with the format parameters separated using a space the   
                 code responsible for parsing will recursively call itself    
                 until it crashes. This occurs as the code does not properly  
                 handle spaces separating the parameters. This does NOT       
                 require the endpoint to have Opus configured in Asterisk.    
                 This also does not require the endpoint to be                
                 authenticated. If guest is enabled for chan_sip or           
                 anonymous in chan_pjsip an SDP offer or answer is still      
                 processed and the crash occurs.                              

    Resolution  The code has been updated to properly handle spaces           
                separating parameters in the fmtp line. Upgrade to a          
                released version with the fix incorporated or apply patch.    

                               Affected Versions 
                      Product                    Release  
                                                 Series   
               Asterisk Open Source               13.x    13.12.0 and higher  
               Asterisk Open Source               14.x    All Versions        

                                  Corrected In               
                            Product                              Release      
                     Asterisk Open Source                    13.13.1, 14.2.1  

                                    Patches                          
                                SVN URL                              Revision 
   http://downloads.asterisk.org/pub/security/AST-2016-008-13.diff   Asterisk 
                                                                     13       
   http://downloads.asterisk.org/pub/security/AST-2016-008-14.diff   Asterisk 
                                                                     14       

    Links  https://issues.asterisk.org/jira/browse/ASTERISK-26579             

    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-2016-008.pdf and             
    http://downloads.digium.com/pub/security/AST-2016-008.html                

                                Revision History
          Date           Editor                  Revisions Made               
    November 15, 2016  Joshua Colp  Initial draft of Advisory                 

               Asterisk Project Security Advisory - AST-2016-008
               Copyright © 2016 Digium, Inc. All Rights Reserved.
  Permission is hereby granted to distribute and publish this advisory in its
                           original, unaltered form.