Bug 1203719 (CVE-2015-1804)

Summary:	CVE-2015-1804 libXfont: out-of-bounds memory access in bdfReadCharacters
Product:	[Other] Security Response	Reporter:	Martin Prpič <mprpic>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	btissoir, fonts-bugs, jshort, sandmann, tfrazier
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	libXfont 1.5.1, libXfont 1.4.9	Doc Type:	Bug Fix
Doc Text:	An integer truncation flaw was discovered in the way libXfont processed certain Glyph Bitmap Distribution Format (BDF) fonts. A malicious, local user could use this flaw to crash the X.Org server or, potentially, execute arbitrary code with the privileges of the X.Org server.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2019-06-08 02:40:11 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:	1203720, 1258892, 1258893, 1258894, 1258895
Bug Blocks:	1203722

Description Martin Prpič 2015-03-19 14:14:03 UTC

The bdf parser read metrics values as 32-bit integers, but stored them into 16-bit integers. Overflows could occur in various operations leading to out-of-bounds memory access.

A local user could exploit this issue to potentially execute arbitrary code with the privileges of the X.Org server.

Upstream patch:

http://cgit.freedesktop.org/xorg/lib/libXfont/commit/?id=2351c83a77a478b49cba6beb2ad386835e264744

External References:

http://www.x.org/wiki/Development/Security/Advisory-2015-03-17/

Comment 1 Martin Prpič 2015-03-19 14:15:14 UTC

Created libXfont tracking bugs for this issue:

Affects: fedora-all [bug 1203720]

Comment 2 Fedora Update System 2015-03-23 07:17:15 UTC

libXfont-1.5.1-1.fc21 has been pushed to the Fedora 21 stable repository.  If problems still persist, please make note of it in this bug report.

Comment 4 errata-xmlrpc 2015-09-03 11:26:59 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7
  Red Hat Enterprise Linux 6

Via RHSA-2015:1708 https://rhn.redhat.com/errata/RHSA-2015-1708.html

Comment 5 ddu 2015-09-07 05:07:51 UTC

Hi guys,

Does this problem CVE affect libXfont shipped with RHEL5?

Best regards,
Dapeng

Comment 6 Matt Goldman 2015-09-07 14:08:32 UTC

Dapeng,

Yes, from the whiteboard RHEL 5 is affected:

  rhel-5/libXfont=affected

However, RHEL 5 has entered Production Phase 3 as of January 31, 2014. As per our errata policy:
    
    "During the Production 3 Phase, Critical impact Security Advisories (RHSAs) and selected Urgent Priority Bug Fix Advisories (RHBAs) may be released as they become available."
    Red Hat Enterprise Linux Life Cycle
    https://access.redhat.com/support/policy/updates/errata#Production_3_Phase

This means that Red Hat will not be addressing Low, Moderate, or Important impact CVE's in relation to RHEL 5.