Bug 1671379 (CVE-2018-19837)

Summary:	CVE-2018-19837 libsass: Stack consumption in Sass::Eval::operator() resulting in a denial of service
Product:	[Other] Security Response	Reporter:	Andrej Nemec <anemec>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	aurelien, fmuellner
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-10-27 03:23:16 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:	1671395, 1671396, 1678800
Bug Blocks:	1671393

Description Andrej Nemec 2019-01-31 14:03:13 UTC

In LibSass prior to 3.5.5, Sass::Eval::operator()(Sass::Binary_Expression*) inside eval.cpp allows attackers to cause a denial-of-service resulting from stack consumption via a crafted sass file, because of certain incorrect parsing of '%' as a modulo operator in parser.cpp.

Upstream issue:

https://github.com/sass/libsass/issues/2659

Upstream patch:

https://github.com/sass/libsass/commit/210fdff7a65370c2ae24e022a2b35da8c423cc5f

Comment 1 Andrej Nemec 2019-01-31 14:16:32 UTC

Created libsass tracking bugs for this issue:

Affects: epel-7 [bug 1671396]
Affects: fedora-all [bug 1671395]