Bug 1191096 (CVE-2014-9673)

Summary:	CVE-2014-9673 freetype: integer signedness error in Mac_Read_POST_Resource() leading to heap-based buffer overflow
Product:	[Other] Security Response	Reporter:	Vasyl Kaigorodov <vkaigoro>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	behdad, fonts-bugs, kevin, mkasik
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	freetype 2.5.4	Doc Type:	Bug Fix
Doc Text:	An integer signedness flaw, leading to a heap-based buffer overflow, was found in the way FreeType handled Mac fonts. If a specially crafted font file was loaded by an application linked against FreeType, it could cause the application to crash or, potentially, execute arbitrary code with the privileges of the user running the application.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2015-03-18 07:40:46 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:	1197737, 1197738, 1197739, 1197740
Bug Blocks:	1191102

Description Vasyl Kaigorodov 2015-02-10 12:52:57 UTC

Common Vulnerabilities and Exposures assigned CVE-2014-9673 to the following issue:

Integer signedness error in the Mac_Read_POST_Resource function in base/ftobjs.c
in FreeType before 2.5.4 allows remote attackers to cause a denial of service
(heap-based buffer overflow) or possibly have unspecified other impact via a
crafted Mac font.

http://code.google.com/p/google-security-research/issues/detail?id=154
http://git.savannah.gnu.org/cgit/freetype/freetype2.git/commit/?id=35252ae9aa1dd9343e9f4884e9ddb1fee10ef415

Comment 1 Tomas Hoger 2015-02-24 20:58:36 UTC

(Private) upstream bug:
https://savannah.nongnu.org/bugs/?43539

Issue was fixed upstream in 2.5.4.

This issue was reported as being a flaw in the boundary check added to fix CVE-2010-2808 (see bug 621907) by using negative rlen value.  However, the check can not be reached with negative rlen, see:

https://code.google.com/p/google-security-research/issues/detail?id=154#c6

There is another signedness issue in the part of the function that computes the amount of memory needed to store font resources.  Negative resource length value can lead to insufficient buffer allocation.  However, this issue is closely related to what was reported as CVE-2014-9674 (bug 1191190).  The boundary between the issues, and whether they need/should to be treated as separate CVEs is not obvious.

Complete upstream fix that was applied to address these two issues is noted in bug 1191190 comment 4.

Comment 4 errata-xmlrpc 2015-03-17 17:59:16 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 6
  Red Hat Enterprise Linux 7

Via RHSA-2015:0696 https://rhn.redhat.com/errata/RHSA-2015-0696.html