Bug 1265998 (CVE-2015-7313)

Summary:	CVE-2015-7313 libtiff: OOM when parsing crafted tiff files
Product:	[Other] Security Response	Reporter:	Martin Prpič <mprpic>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED WONTFIX	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	carnil, erik-fedora, federicoleva, jrusnack, phracek
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2015-10-07 13:49:58 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:	1265999, 1266000
Bug Blocks:	1266001

Description Martin Prpič 2015-09-24 09:36:53 UTC

A denial of service flaw was found in the way libtiff parsed certain tiff files. An attacker could use this flaw to create a specially crafted TIFF file that would cause an application using libtiff to exhaust all available memory on the system.

Original report:

http://seclists.org/oss-sec/2015/q3/601

Comment 1 Martin Prpič 2015-09-24 09:37:49 UTC

Created libtiff tracking bugs for this issue:

Affects: fedora-all [bug 1265999]

Comment 2 Martin Prpič 2015-09-24 09:37:54 UTC

Created mingw-libtiff tracking bugs for this issue:

Affects: fedora-all [bug 1266000]

Comment 3 Stefan Cornelius 2015-10-07 10:48:48 UTC

On Fedora and RHEL7, disabling memory overcommit (echo 2 > /proc/sys/vm/overcommit_memory) seems to "fix" this issue. Thus, there is nothing wrong with the libtiff code. Instead, the memory overcommit will prevent certain memory errors to be passed to the libtiff code, ultimately "bypassing" the libtiff error checks, leading to an OOM kill instead of a libtiff exit.


On RHEL6, it detects and integer overflow and exits:
TIFFReadDirectory: Warning, oom.tif: Bogus "StripByteCounts" field, ignoring and calculating from imagelength.
oom.tif: Integer overflow in TIFFVStripSize.
TIFFReadDirectory: oom.tif: cannot handle zero strip size.

Comment 4 Federico Leva 2015-10-26 14:45:28 UTC

A variant with "bus error" was seen libtiff 3.4 http://markmail.org/message/igqy46wj7kzhnkjv