Bug 1870162 (CVE-2020-16307)

Summary:	CVE-2020-16307 ghostscript: NULL pointer dereference in devices/vector/gdevtxtw.c and psi/zbfont.c could result in a DoS
Product:	[Other] Security Response	Reporter:	Michael Kaplan <mkaplan>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	amasferr, chazlett, deekej, jlyle, mosvald, twaugh, zdohnal
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	ghostscript 9.51	Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-05-18 20:34:56 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:	1870163, 1870851, 1870852
Bug Blocks:	1870273

Description Michael Kaplan 2020-08-19 13:13:23 UTC

A null pointer dereference vulnerability in devices/vector/gdevtxtw.c and psi/zbfont.c of Artifex Software GhostScript v9.50 allows a remote attacker to cause a denial of service via a crafted postscript file. This is fixed in v9.51.

Reference:

http://git.ghostscript.com/?p=ghostpdl.git;a=commitdiff;h=407c98a38c3a6ac1681144ed45cc2f4fc374c91f
https://bugs.ghostscript.com/show_bug.cgi?id=701822

Comment 1 Michael Kaplan 2020-08-19 13:14:06 UTC

Created ghostscript tracking bugs for this issue:

Affects: fedora-all [bug 1870163]

Comment 4 Todd Cullum 2020-08-21 15:06:56 UTC

Flaw summary:

A segmentation fault occurs when get_unicode() in /devices/vector/gdevtxtw.c and gs_font_map_glyph_to_unicode() in /psi/zbfont.c are called with the GS_NO_GLYPH glyph value. These functions are used for handling Unicode glyphs. The patch adds checks to the above routines to avoid processing the invalid GS_NO_GLYPH value.

Comment 5 Todd Cullum 2020-08-21 15:09:06 UTC

Mitigation:

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

Comment 6 errata-xmlrpc 2021-05-18 15:36:37 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2021:1852 https://access.redhat.com/errata/RHSA-2021:1852

Comment 7 Product Security DevOps Team 2021-05-18 20:34:56 UTC

This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):

https://access.redhat.com/security/cve/cve-2020-16307