Cisco ASA Next-Generation Firewall fragment Message Denial of Service Vulnerability

Release date:
Updated on: 2013-06-27

Affected Systems:
Cisco Next-Generation Firewall
Description:
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CVE (CAN) ID: CVE-2013-3382
 
Cisco ASA Next-Generation Firewall is a Next-Generation Firewall product. It is an additional service module that extends the ASA platform.
 
The implementation of Cisco ASA Next-Generation Firewall has a shard Message Denial-of-Service vulnerability, which can cause device heavy load or stop checking the user messages sent from the parent Cisco ASA to the asa ngfw module. This vulnerability is caused by Invalid resolution and reorganization packets. Attackers exploit this vulnerability by sending fragmented packets to the asa ngfw denial policy.
 
<* Source: vendor

Link: http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20130626-ngfw
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Suggestion:
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Temporary solution:
 
If you cannot install or upgrade the patch immediately, NSFOCUS recommends that you take the following measures to reduce the threat:
 
* Disable the Cisco ASA firewall to redirect Web traffic to the Cisco asa ngfw module:
ASA (config) # policy-map cx_traffic_policy
ASA (config-pmap) # class cx_traffic
ASA (config-pmap-c) # no cxcs
* Disable fragment Message Processing for Cisco ASA firewall:
ASA (config) # fragment chain 1
 
Vendor patch:
 
Cisco
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Cisco has released a Security Bulletin (cisco-sa-20130626-ngfw) and patches for this:
Cisco-sa-20130626-ngfw: Cisco ASA Next-Generation Firewall Fragmented Traffic Denial of Service Vulnerability
Link: http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20130626-ngfw