Bug 1621363 (CVE-2018-16542)

Summary:	CVE-2018-16542 ghostscript: .definemodifiedfont memory corruption if /typecheck is handled (699668)
Product:	[Other] Security Response	Reporter:	Stefan Cornelius <scorneli>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	mosvald, security-response-team, twaugh, zdohnal
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	ghostscript 9.24	Doc Type:	If docs needed, set a value
Doc Text:	It was discovered that ghostscript did not properly handle certain stack overflow error conditions. An attacker could possibly exploit this to bypass the -dSAFER protection and crash ghostscript or, possibly, execute arbitrary code in the ghostscript context via a specially crafted PostScript document.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2018-11-20 10:33:01 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:	1621380, 1621382, 1625827, 1625828
Bug Blocks:	1619570

Description Stefan Cornelius 2018-08-23 15:24:15 UTC

It was discovered that ghostscript did not properly handle certain stack overflow error conditions. A specially crafted PostScript document could exploit this to crash ghostscript or, possibly, execute arbitrary code in the context of the ghostscript process.

Patch:
http://git.ghostscript.com/?p=ghostpdl.git;a=commitdiff;h=b575e1ec42

Comment 3 Sam Fowler 2018-09-06 04:44:57 UTC

Created ghostscript tracking bugs for this issue:

Affects: fedora-all [bug 1625827]

Comment 6 Stefan Cornelius 2018-09-19 08:23:20 UTC

Acknowledgments:

Name: Tavis Ormandy (Google Project Zero)

Comment 7 errata-xmlrpc 2018-10-16 02:25:35 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2018:2918 https://access.redhat.com/errata/RHSA-2018:2918

Comment 8 Cedric Buissart 2018-11-20 10:32:22 UTC

Statement:

This issue affects the versions of ghostscript as shipped with Red Hat Enterprise Linux 5, 6, and 7.

Red Hat Enterprise Linux 6 is now in Maintenance Support 2 Phase of the support and maintenance life cycle. This has been rated as having a security impact of Important, and is not currently planned to be addressed in future updates. For additional information, refer to the Red Hat Enterprise Linux Life Cycle: https://access.redhat.com/support/policy/updates/errata/.

Red Hat Enterprise Linux 5 is now in Extended Life Phase of the support and maintenance life cycle. This issue is not currently planned to be addressed in future updates. For additional information, refer to the Red Hat Enterprise Linux Life Cycle: https://access.redhat.com/support/policy/updates/errata/.

Comment 9 Cedric Buissart 2018-11-20 10:33:09 UTC

Mitigation:

Please refer to the "Mitigation" section of CVE-2018-16509 : https://access.redhat.com/security/cve/cve-2018-16509