Cisco Cisco Firepower Management Center 4000

When the resource record type is TXT (text), the RData field is a variable-length ASCII text field.

When selected, the DNS preprocessor 

 option detects a specific 

vulnerability identified by entry CVE-2006-3441 in MITRE’s Current Vulnerabilities and Exposures 
database. This is a known vulnerability in Microsoft Windows 2000 Service Pack 4, Windows XP 
Service Pack 1 and Service Pack 2, and Windows Server 2003 Service Pack 1. An attacker can exploit 
this vulnerability and take complete control of a host by sending or otherwise causing the host to receive 
a maliciously crafted name server response that causes a miscalculation in the length of an RData text 
field, resulting in a buffer overflow.

You should enable this feature when your network might include hosts running operating systems that 
have not been upgraded to correct this vulnerability.

You can enable rule 131:3 to generate events for this option. See 

 for 

more information.

Protection

RFC 1035 identifies several resource record types as obsolete. Because these are obsolete record types, 
some systems do not account for them and may be open to exploits. You would not expect to encounter 
these record types in normal DNS responses unless you have purposely configured your network to 
include them.

You can configure the system to detect known obsolete resource record types. The following table lists 
and describes these record types.

You can enable rule 131:1 to generate events for this option. See 

 for 

more information.

Protection

RFC 1035 identifies several resource record types as experimental. Because these are experimental 
record types, some systems do not account for them and may be open to exploits. You would not expect 
to encounter these record types in normal DNS responses unless you have purposely configured your 
network to include them.

You can configure the system to detect known experimental resource record types. The following table 
lists and describes these record types.

3

MD

a mail destination

4

MF

a mail forwarder