Bug 1894691 (CVE-2020-27770)

Summary:	CVE-2020-27770 ImageMagick: unsigned offset overflowed at MagickCore/string.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:	Due to a missing check for 0 value of `replace_extent`, it is possible for offset `p` to overflow in SubstituteString(), causing potential impact to application availability. This could be triggered by a crafted input file that is processed by ImageMagick.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2020-11-24 23:35:18 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:	1901285, 1901286, 1910534
Bug Blocks:	1891602

Description Guilherme de Almeida Suckevicz 2020-11-04 19:21:56 UTC

In ImageMagick, there is an integer overflow in MagickCore/string.c.

Reference:
https://github.com/ImageMagick/ImageMagick/issues/1721

Upstream patch:
https://github.com/ImageMagick/ImageMagick/commit/be90a5395695f0d19479a5d46b06c678be7f7927

Comment 1 Guilherme de Almeida Suckevicz 2020-11-04 19:21:58 UTC

Acknowledgments:

Name: Suhwan Song (Seoul National University)

Comment 2 Todd Cullum 2020-11-05 23:06:54 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 .

Comment 3 Todd Cullum 2020-11-05 23:12:33 UTC

Flaw summary:

Due to a missing check for 0 value of `replace_extent`, it is possible for offset `p` to overflow in SubstituteString(), causing potential impact to application availability. This could be triggered by a crafted input file that is processed by ImageMagick.

Comment 4 Guilherme de Almeida Suckevicz 2020-11-24 19:28:48 UTC

Created ImageMagick tracking bugs for this issue:

Affects: epel-8 [bug 1901285]
Affects: fedora-all [bug 1901286]

Comment 5 Product Security DevOps Team 2020-11-24 23:35:18 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-2020-27770