Bug 224445

Summary: CVE-2007-0493 BIND might crash after attempting to read free()-ed memory
Product: Red Hat Enterprise Linux 5 Reporter: Lubomir Kundrak <lkundrak>
Component: bindAssignee: Adam Tkac <atkac>
Status: CLOSED ERRATA QA Contact: Ben Levenson <benl>
Severity: low Docs Contact:
Priority: low    
Version: 5.0CC: atkac, ovasik
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
URL: http://marc.theaimsgroup.com/?l=bind-announce&m=116968519321296&w=2
Whiteboard: impact=low,source=gentoo,public=20070125,reported=20070125,versions=5
Fixed In Version: RHSA-2007-0057 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2007-03-14 14:55:27 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 230003, 238117    
Attachments:
Description Flags
proposed fix none

Description Lubomir Kundrak 2007-01-25 19:06:43 UTC 
+++ This bug was initially created as a clone of Bug #224443 +++

Description of problem:

fetchctx structures,  not keeping count of its uses, might be read
even after beind deallocated resulting in name server denial of
service under certain circumstances.

Version-Release number of selected component (if applicable):

Unclear whether this issue also affects 3.2 BIND, besides 3.3.
For sure affects FC-5, FC-6 and RHEL-5

How reproducible:

Hardly ever.

Steps to Reproduce:

No known way to reproduce. The advisory notes, that the issue can be
partly mitigated by disabling recursion, so probably some deep recursive
queries might trigger the bug?
  
Actual results:

Server DoS?

Expected results:

What would you expect from read of deallocated memory? :)

Additional info:

ISC is not particularly good at providing either patches or information
about the flaws. The attached patch incorporates another fix which
changes roughly the same code.

-- Additional comment from lkundrak on 2007-01-25 14:04 EST --
Created an attachment (id=146596)
Fix for BIND out-of bound read DoS sucked from upstream BIND release
Comment 1 Martin Stransky 2007-01-31 14:12:05 UTC 
Created attachment 147023 [details]
proposed fix
Comment 5 Red Hat Bugzilla 2007-03-14 14:55:27 UTC 
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on the solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHSA-2007-0057.html
Comment 7 Adam Tkac 2007-05-24 12:46:27 UTC 
*** Bug 238117 has been marked as a duplicate of this bug. ***