CVE-2000-0887: zxfr bug

A bug in code intended to provide support for the transfer of compressed zone files can result in the name server crashing.

          CVE: 


                [CVE-2000-0887](http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2000-0887)        


    







        
                  
          CERT: 


                [VU#715973](http://www.kb.cert.org/vuls/id/715973)        


    







        
                  
          Posting date: 


                10 Nov 2000        


    







        
                  
          Program Impacted: 


                [BIND](https://www.isc.org/software/bind)        


    







        
                  
          Versions affected: 


                 8.2.2 - 8.2.2-p6        


    







        
                  
          Severity: 


                Serious        


    







        
                  
          Exploitable: 


                Remotely        


    






  Description: 



        
                named in BIND 8.2 through 8.2.2-P6 allows remote 

attackers to cause a denial of service by making a compressed zone transfer (ZXFR) request and performing a name service query on an authoritative record that is not cached, aka the "zxfr bug." This will disrupt name resolution service until the named daemon is restarted.

  Workarounds: 



        
                A partial workaround can be implemented by 

disallowing zone transfers except from trusted hosts. Note that if the trusted hosts are compromised, name servers with this bug will be vulnerable to denial of service attacks.

  Active exploits: 



        
                This attack can be implemented using utilities provided with the BIND package (named-xfer and dig).        


    






  Solution: 



        
                Upgrade to 8.2.2-p7 or later. 


    


    

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