Versions of Rails::Html::Sanitizer prior to version 1.4.3 are vulnerable to XSS with certain configurations of Rails::Html::Sanitizer which allows an attacker to inject content when the application developer has overridden the sanitizer’s allowed tags to allow both select
and style
elements. Code is only impacted if allowed tags are being overridden.
This may be done via application configuration: ruby# In config/application.rbconfig.action_view.sanitized_allowed_tags = ["select", "style"]
see https://guides.rubyonrails.org/configuring.html#configuring-action-view
Or it may be done with a :tags
option to the Action View helper sanitize
: <%= sanitize @comment.body, tags: ["select", "style"] %>
see https://api.rubyonrails.org/classes/ActionView/Helpers/SanitizeHelper.html#method-i-sanitize
It may also be done with Rails::Html::SafeListSanitizer directly:
ruby# class-level optionRails::Html::SafeListSanitizer.allowed_tags = ["select", "style"]
or with
ruby# instance-level optionRails::Html::SafeListSanitizer.new.sanitize(@article.body, tags: ["select", "style"])
All users overriding the allowed tags by any of the above mechanisms to include both “select” and “style” are recommended to upgrade immediately. A workaround for this issue can be applied by removing either select
or style
from the overridden allowed tags.
github.com/rails/rails-html-sanitizer
github.com/rails/rails-html-sanitizer/commit/45a5c10fed3d9aa141594c80afa06d748fa0967d
github.com/rubysec/ruby-advisory-db/blob/master/gems/rails-html-sanitizer/CVE-2022-32209.yml
groups.google.com/g/rubyonrails-security/c/ce9PhUANQ6s
hackerone.com/reports/1530898
lists.debian.org/debian-lts-announce/2022/12/msg00012.html
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AGRLWBEB3S5AU3D4TTROIS7O6QPHDTRH
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NHDACMCLWE32BZZTSNWQPIFUAD5I6Q47
lists.fedoraproject.org/archives/list/[email protected]/message/AGRLWBEB3S5AU3D4TTROIS7O6QPHDTRH
lists.fedoraproject.org/archives/list/[email protected]/message/NHDACMCLWE32BZZTSNWQPIFUAD5I6Q47
nvd.nist.gov/vuln/detail/CVE-2022-32209