---
title: "CVE-2002-1221: BIND 8 fails to properly dereference cache SIG RR elements with invalid expiry times"
slug: "aa-00954"
description: "Remote attackers can cause a denial of service (crash) via SIG RR elements with invalid expiry times, which are removed from the internal BIND database and later cause a null dereference."
updated: 2021-08-04T21:51:31Z
published: 2021-08-04T21:51:31Z
---

> ## Documentation Index
> Fetch the complete documentation index at: https://kb.isc.org/llms.txt
> Use this file to discover all available pages before exploring further.

# CVE-2002-1221: BIND 8 fails to properly dereference cache SIG RR elements with invalid expiry times

De-referencing null pointer for certain signature expire values.        
        




    
            
                      
              CVE: 


                    [CVE-2002-1221](http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2002-1221)        


        






    
            
                      
              CERT: 


                    [VU#581682](http://www.kb.cert.org/vuls/id/581682)        


        






    
            
                      
              Posting date: 


                    12 Nov 2002        


        






    
            
                      
              Program Impacted: 


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


        






    
            
                      
              Versions affected: 


                    8.3.0 - 8.3.3        


        






    
            
                      
              Severity: 


                    Serious        


        






    
            
                      
              Exploitable: 


                    Remotely        


        






      Description: 


    
            
                    Remote attackers can cause a denial of service 
(crash) via SIG RR elements with invalid expiry times, which are removed
 from the internal BIND database and later cause a null dereference. 


        


        






      Workarounds: 


    
            
                    Disable recursion, if possible.


        


        






      Active exploits: 


    
            
                    None known at this time.        


        






      Solution: 


    
            
                    Upgrade to BIND 8.3.4 or later


        


        






    
            
                    **Acknowledgements:** 


ISC would like to thank Internet Security Systems for bringing this to our attention.


        


        












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