Asterisk Project Security Advisory - AST-2017-010

         Product        Asterisk                                              
         Summary        Buffer overflow in CDR's set user                     
    Nature of Advisory  Buffer Overflow                                       
      Susceptibility    Remote Authenticated Sessions                         
         Severity       Moderate                                              
      Exploits Known    No                                                    
       Reported On      October 9, 2017                                       
       Reported By      Richard Mudgett                                       
        Posted On       
     Last Updated On    October 25, 2017                                      
     Advisory Contact   Rmudgett AT digium DOT com                            
         CVE Name       

    Description  No size checking is done when setting the user field for     
                 Party B on a CDR. Thus, it is possible for someone to use    
                 an arbitrarily large string and write past the end of the    
                 user field storage buffer. The earlier AST-2017-001          
                 advisory for the CDR user field overflow was for the Party   
                 A buffer.                                                    
                                                                              
                 This currently affects any system using CDR's that also      
                 make use of the following:                                   
                                                                              
                 * The 'X-ClientCode' header within a SIP INFO message when   
                 using chan_sip and                                           
                                                                              
                 the 'useclientcode' option is enabled (note, it's disabled   
                 by default).                                                 
                                                                              
                 * The CDR dialplan function executed from AMI when setting   
                 the user field.                                              
                                                                              
                 * The AMI Monitor action when using a long file name/path.   

    Resolution  The CDR engine now only copies up to the maximum allowed      
                characters into the user field. Any characters outside the    
                maximum are truncated.                                        

                               Affected Versions       
                         Product                       Release  
                                                       Series   
                  Asterisk Open Source                  13.x    All Releases  
                  Asterisk Open Source                  14.x    All Releases  
                  Asterisk Open Source                  15.x    All Releases  
                   Certified Asterisk                   13.13   All Releases  

                                  Corrected In
          Product                              Release                        
    Asterisk Open Source               13.18.1, 14.7.1, 15.1.1                
     Certified Asterisk                      13.13-cert7                      

                                     Patches                          
                                SVN URL                               Revision  
   http://downloads.asterisk.org/pub/security/AST-2017-010-13.diff    Asterisk  
                                                                      13        
   http://downloads.asterisk.org/pub/security/AST-2017-010-14.diff    Asterisk  
                                                                      14        
   http://downloads.asterisk.org/pub/security/AST-2017-010-15.diff    Asterisk  
                                                                      15        
   http://downloads.asterisk.org/pub/security/AST-2017-010-13.13.diff Certified 
                                                                      Asterisk  
                                                                      13.13     

    Links  https://issues.asterisk.org/jira/browse/ASTERISK-27337             

    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-2017-010.pdf and             
    http://downloads.digium.com/pub/security/AST-2017-010.html                

                                Revision History
                    Date                       Editor        Revisions Made   
    October 12, 2017                       Richard Mudgett  Initial Revision  

               Asterisk Project Security Advisory - AST-2017-010
               Copyright A(c) 2017 Digium, Inc. All Rights Reserved.
  Permission is hereby granted to distribute and publish this advisory in its
                           original, unaltered form.