GHSA-9h9g-93gc-623h

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Source
https://github.com/advisories/GHSA-9h9g-93gc-623h
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2022/12/GHSA-9h9g-93gc-623h/GHSA-9h9g-93gc-623h.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-9h9g-93gc-623h
Aliases
Published
2022-12-13T17:50:25Z
Modified
2023-11-01T04:57:53.607092Z
Severity
  • 6.1 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N CVSS Calculator
Summary
Possible XSS vulnerability with certain configurations of rails-html-sanitizer
Details

Summary

There is a possible XSS vulnerability with certain configurations of Rails::Html::Sanitizer.

  • Versions affected: ALL
  • Not affected: NONE
  • Fixed versions: 1.4.4

Impact

A possible XSS vulnerability with certain configurations of Rails::Html::Sanitizer may allow an attacker to inject content if the application developer has overridden the sanitizer's allowed tags in either of the following ways:

  • allow both "math" and "style" elements,
  • or allow both "svg" and "style" elements

Code is only impacted if allowed tags are being overridden. Applications may be doing this in four different ways:

  1. using application configuration:

    # In config/application.rb
    config.action_view.sanitized_allowed_tags = ["math", "style"]
    # or
    config.action_view.sanitized_allowed_tags = ["svg", "style"]
    

    see https://guides.rubyonrails.org/configuring.html#configuring-action-view

  2. using a :tags option to the Action View helper sanitize:

    <%= sanitize @comment.body, tags: ["math", "style"] %>
    <%# or %>
    <%= sanitize @comment.body, tags: ["svg", "style"] %>
    

    see https://api.rubyonrails.org/classes/ActionView/Helpers/SanitizeHelper.html#method-i-sanitize

  3. using Rails::Html::SafeListSanitizer class method allowed_tags=:

    # class-level option
    Rails::Html::SafeListSanitizer.allowed_tags = ["math", "style"]
    # or
    Rails::Html::SafeListSanitizer.allowed_tags = ["svg", "style"]
    
  4. using a :tags options to the Rails::Html::SafeListSanitizer instance method sanitize:

    # instance-level option
    Rails::Html::SafeListSanitizer.new.sanitize(@article.body, tags: ["math", "style"])
    # or
    Rails::Html::SafeListSanitizer.new.sanitize(@article.body, tags: ["svg", "style"])
    

All users overriding the allowed tags by any of the above mechanisms to include (("math" or "svg") and "style") should either upgrade or use one of the workarounds immediately.

Workarounds

Remove "style" from the overridden allowed tags, or remove "math" and "svg" from the overridden allowed tags.

References

Credit

This vulnerability was responsibly reported by Dominic Breuker.

References

Affected packages

RubyGems / rails-html-sanitizer

Package

Name
rails-html-sanitizer
Purl
pkg:gem/rails-html-sanitizer

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.4.4

Affected versions

1.*

1.0.0
1.0.1
1.0.2
1.0.3
1.0.4
1.1.0
1.2.0
1.3.0
1.4.0
1.4.1
1.4.2
1.4.3