Bug 842420 (CVE-2012-3571)

Summary: CVE-2012-3571 dhcp: DoS due to error in handling malformed client identifiers
Product: [Other] Security Response Reporter: Vincent Danen <vdanen>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: jpopelka, ljozsa, security-response-team
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard: impact=moderate,public=20120724,reported=20120723,source=upstream,cvss2=3.3/AV:A/AC:L/Au:N/C:N/I:N/A:P,fedora-all/dhcp=affected,rhel-6/dhcp=affected,rhel-5/dhcp=affected
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: ---
Bug Depends On: 842892, 843120, 843122, 843124, 843125    
Bug Blocks: 842431    

Description Vincent Danen 2012-07-23 16:19:02 EDT
An error in the handling of malformed client identifiers can cause a DHCP
server running affected versions to enter a state where further client
requests are not processed and the server process loops endlessly,
consuming all available CPU cycles.

Under normal circumstances this condition should not be triggered, but a
non-conforming or malicious client could deliberately trigger it in a
vulnerable server. In order to exploit this condition an attacker must be
able to send requests to the DHCP server .

ISC DHCP versions 4.2.x through to 4.2.4 are affected, as well as 4.1.x.  Earlier versions may also be vulnerable.

Acknowledgements:

Upstream acknowledges Markus Hietava of Codenomicon CROSS project as the original reporter of this issue.
Comment 2 Vincent Danen 2012-07-24 16:35:56 EDT
This is now public:

https://kb.isc.org/article/AA-00712
Comment 3 Vincent Danen 2012-07-24 16:37:40 EDT
Created dhcp tracking bugs for this issue

Affects: fedora-all [bug 842892]
Comment 10 Fedora Update System 2012-08-01 14:27:59 EDT
dhcp-4.2.4-9.P1.fc17 has been pushed to the Fedora 17 stable repository.  If problems still persist, please make note of it in this bug report.
Comment 11 errata-xmlrpc 2012-08-02 20:28:00 EDT
This issue has been addressed in following products:

  Red Hat Enterprise Linux 6

Via RHSA-2012:1141 https://rhn.redhat.com/errata/RHSA-2012-1141.html
Comment 12 errata-xmlrpc 2012-08-02 20:28:08 EDT
This issue has been addressed in following products:

  Red Hat Enterprise Linux 5

Via RHSA-2012:1140 https://rhn.redhat.com/errata/RHSA-2012-1140.html
Comment 13 Fedora Update System 2012-08-06 03:50:19 EDT
dhcp-4.2.3-11.P2.fc16 has been pushed to the Fedora 16 stable repository.  If problems still persist, please make note of it in this bug report.