Bug 1891928 (CVE-2020-25674)

Summary:	CVE-2020-25674 ImageMagick: heap-based buffer overflow in WriteOnePNGImage in coders/png.c
Product:	[Other] Security Response	Reporter:	Guilherme de Almeida Suckevicz <gsuckevi>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED WONTFIX	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	fedora, jhorak, mike, pahan, rhel8-maint, security-response-team, stransky
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	ImageMagick 7.0.8-68	Doc Type:	If docs needed, set a value
Doc Text:	A flaw was found in ImageMagick. When the colormap has less than 256 valid values, the loop condition will continue to loop 256 times, attempting to pass invalid colormap data to the event logger, leading to an improper exit condition and an out-of-bounds read via heap-buffer-overflow. The highest threat from this vulnerability is to system availability.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2020-11-24 23:34:08 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:	1901233, 1901235, 1910560
Bug Blocks:	1891602

Description Guilherme de Almeida Suckevicz 2020-10-27 17:17:29 UTC

In ImageMagick 7.0.8-67 there is a heap-buffer-overflow at coders/png.c:9026:46 in WriteOnePNGImage.

Reference:
https://github.com/ImageMagick/ImageMagick/issues/1715

Upstream patch:
https://github.com/ImageMagick/ImageMagick/commit/67b871032183a29d3ca0553db6ce1ae80fddb9aa

Comment 1 Todd Cullum 2020-10-28 21:45:38 UTC

Flaw summary:

WriteOnePNGImage() from coders/png.c (the PNG coder) has a for loop with an improper exit condition that can allow an out-of-bounds READ via heap-buffer-overflow. This occurs because it is possible for the colormap to have less than 256 valid values but the loop condition will loop 256 times, attempting to pass invalid colormap data to the event logger. The patch replaces the hardcoded 256 value with a call to MagickMin() to ensure the proper value is used.

This could impact application availability when a specially crafted input file is processed by ImageMagick.

Comment 2 Todd Cullum 2020-10-28 21:49:20 UTC

Acknowledgments:

Name: Suhwan Song (Seoul National University)

Comment 4 Guilherme de Almeida Suckevicz 2020-11-24 19:04:11 UTC

Created ImageMagick tracking bugs for this issue:

Affects: epel-8 [bug 1901233]
Affects: fedora-all [bug 1901235]

Comment 5 Product Security DevOps Team 2020-11-24 23:34:08 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-2020-25674

Comment 7 Eric Christensen 2021-02-11 18:43:24 UTC

Statement:

This flaw is out of support scope for Red Hat Enterprise Linux 5, 6, and 7. Inkscape is not affected because it no longer uses a bundled ImageMagick in Red Hat Enterprise Linux 8. For more information regarding support scopes, please see https://access.redhat.com/support/policy/updates/errata.