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CVE-2011-2748: ISC DHCP Server Halt
Author: Michael McNally Reference Number: AA-00454 Views: 3729 Created: 2011-09-09 23:10 Last Updated: 2012-06-08 13:36 0 Rating/ Voters

ISC DHCP Server Halt

Two issues have been found in DHCP that could allow an attacker to cause the server to halt.
Document Version: 
Posting date: 
10 Aug 2011
Program Impacted: 
Versions affected: 
3.1.0 through 3.1-ESV-R1 (R2 never released) 4.0 all versions (EOL) 4.1.0 through 4.1.2rc1 4.1-ESV through 4.1-ESV-R3b1 4.2.0 through 4.2.2rc1 All End-of-Life versions of DHCP server are likely to be affected and ISC recommends upgrading to supported versions.

A pair of defects cause the server to halt upon processing certain packets. The patch is to properly discard or process those packets. 

Document ID: CVE-2011-2748, CVE-2011-2749

CVSS Score: 7.8

CVSS Equation: (AV:N/AC:L/Au:N/C:N/I:N/A:C)

For more information on the Common Vulnerability Scoring System and to obtain your specific environmental score please visit:


Limiting DHCP and Bootp packets to only within your administrative domain will limit exposure.

Active exploits: 
ISC received a report for one of the flaws and discovered the other during testing. No public exploits using these bugs are known.

Upgrade to: 3.1-ESV-R3, 4.1-ESV-R3 or 4.2.2 

Please note that this is the last update to 3.1-ESV as it will be End-of-Life after this release. 

Download these versions from

Found by David Zych at University of Illinois

Document Revision History

1.0 27 July 2011 - Phase 1 disclosure

1.1 09 August 2011 - Phase 2 and 3 disclosures

Releated Document: 


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