Bug 1849072 (CVE-2020-4054)

Summary:	CVE-2020-4054 rubygem-rails-html-sanitizer: XSS via crafted input
Product:	[Other] Security Response	Reporter:	Dhananjay Arunesh <darunesh>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED UPSTREAM	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	jaruga, pvalena, ruby-packagers-sig, strzibny, vondruch
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:	2020-06-19 17:20:34 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:	1849073
Bug Blocks:

Description Dhananjay Arunesh 2020-06-19 14:40:12 UTC

In Sanitize (RubyGem sanitize) greater than or equal to 3.0.0 and less than 5.2.1, there is a cross-site scripting vulnerability. When HTML is sanitized using Sanitize's "relaxed" config, or a custom config that allows certain elements, some content in a math or svg element may not be sanitized correctly even if math and svg are not in the allowlist. You are likely to be vulnerable to this issue if you use Sanitize's relaxed config or a custom config that allows one or more of the following HTML elements: iframe, math, noembed, noframes, noscript, plaintext, script, style, svg, xmp. Using carefully crafted input, an attacker may be able to sneak arbitrary HTML through Sanitize, potentially resulting in XSS (cross-site scripting) or other undesired behavior when that HTML is rendered in a browser. This has been fixed in 5.2.1.

References:
https://github.com/rgrove/sanitize/commit/a11498de9e283cd457b35ee252983662f7452aa9
https://github.com/rgrove/sanitize/releases/tag/v5.2.1
https://github.com/rgrove/sanitize/security/advisories/GHSA-p4x4-rw2p-8j8m

Comment 1 Dhananjay Arunesh 2020-06-19 14:40:40 UTC

Created rubygem-rails-html-sanitizer tracking bugs for this issue:

Affects: fedora-all [bug 1849073]

Comment 2 Product Security DevOps Team 2020-06-19 17:20:34 UTC

This CVE Bugzilla entry is for community support informational purposes only as it does not affect a package in a commercially supported Red Hat product. Refer to the dependent bugs for status of those individual community products.

Comment 3 Vít Ondruch 2020-11-03 15:12:52 UTC

I wonder, what was the reason to report this against rails-html-saitizer, because the original description describes something completely different. But possibly, the issue could have been:

https://snyk.io/vuln/SNYK-RUBY-RAILSHTMLSANITIZER-22025

However, this was resolved as CVE-2018-3741.

Comment 4 Vít Ondruch 2020-11-03 15:13:24 UTC

This was very likely misreported.

Comment 5 Vít Ondruch 2020-11-03 15:14:24 UTC

Sorry, wanted to change the Fedora tracker ...