ghsa-9h9g-93gc-623h
Vulnerability from github
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:
- using application configuration:
ruby
# 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
- using a
:tagsoption to the Action View helpersanitize:
<%= 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
- using Rails::Html::SafeListSanitizer class method
allowed_tags=:
ruby
# class-level option
Rails::Html::SafeListSanitizer.allowed_tags = ["math", "style"]
# or
Rails::Html::SafeListSanitizer.allowed_tags = ["svg", "style"]
- using a
:tagsoptions to the Rails::Html::SafeListSanitizer instance methodsanitize:
ruby
# 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
- CWE - CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') (4.9)
- https://hackerone.com/reports/1656627
Credit
This vulnerability was responsibly reported by Dominic Breuker.
{
"affected": [
{
"package": {
"ecosystem": "RubyGems",
"name": "rails-html-sanitizer"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.4.4"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2022-23519"
],
"database_specific": {
"cwe_ids": [
"CWE-79"
],
"github_reviewed": true,
"github_reviewed_at": "2022-12-13T17:50:25Z",
"nvd_published_at": "2022-12-14T17:15:00Z",
"severity": "MODERATE"
},
"details": "## Summary\n\nThere is a possible XSS vulnerability with certain configurations of Rails::Html::Sanitizer.\n\n- Versions affected: ALL\n- Not affected: NONE\n- Fixed versions: 1.4.4\n\n\n## Impact\n\nA 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\u0027s allowed tags in either of the following ways:\n\n- allow both \"math\" and \"style\" elements,\n- or allow both \"svg\" and \"style\" elements\n\nCode is only impacted if allowed tags are being overridden. Applications may be doing this in four different ways:\n\n1. using application configuration:\n\n ```ruby\n # In config/application.rb\n config.action_view.sanitized_allowed_tags = [\"math\", \"style\"]\n # or\n config.action_view.sanitized_allowed_tags = [\"svg\", \"style\"]\n ```\n\n see https://guides.rubyonrails.org/configuring.html#configuring-action-view\n\n2. using a `:tags` option to the Action View helper `sanitize`:\n\n ```\n \u003c%= sanitize @comment.body, tags: [\"math\", \"style\"] %\u003e\n \u003c%# or %\u003e\n \u003c%= sanitize @comment.body, tags: [\"svg\", \"style\"] %\u003e\n ```\n\n see https://api.rubyonrails.org/classes/ActionView/Helpers/SanitizeHelper.html#method-i-sanitize\n\n3. using Rails::Html::SafeListSanitizer class method `allowed_tags=`:\n\n ```ruby\n # class-level option\n Rails::Html::SafeListSanitizer.allowed_tags = [\"math\", \"style\"]\n # or\n Rails::Html::SafeListSanitizer.allowed_tags = [\"svg\", \"style\"]\n ```\n\n4. using a `:tags` options to the Rails::Html::SafeListSanitizer instance method `sanitize`:\n\n ```ruby\n # instance-level option\n Rails::Html::SafeListSanitizer.new.sanitize(@article.body, tags: [\"math\", \"style\"])\n # or\n Rails::Html::SafeListSanitizer.new.sanitize(@article.body, tags: [\"svg\", \"style\"])\n ```\n\nAll 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.\n\n\n## Workarounds\n\nRemove \"style\" from the overridden allowed tags, or remove \"math\" and \"svg\" from the overridden allowed tags.\n\n\n## References\n\n- [CWE - CWE-79: Improper Neutralization of Input During Web Page Generation (\u0027Cross-site Scripting\u0027) (4.9)](https://cwe.mitre.org/data/definitions/79.html)\n- https://hackerone.com/reports/1656627\n\n\n## Credit\n\nThis vulnerability was responsibly reported by Dominic Breuker.\n",
"id": "GHSA-9h9g-93gc-623h",
"modified": "2022-12-17T00:32:41Z",
"published": "2022-12-13T17:50:25Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/rails/rails-html-sanitizer/security/advisories/GHSA-9h9g-93gc-623h"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-23519"
},
{
"type": "WEB",
"url": "https://hackerone.com/reports/1656627"
},
{
"type": "PACKAGE",
"url": "https://github.com/rails/rails-html-sanitizer"
},
{
"type": "WEB",
"url": "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/rails-html-sanitizer/CVE-2022-23519.yml"
},
{
"type": "WEB",
"url": "https://lists.debian.org/debian-lts-announce/2023/09/msg00012.html"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "Possible XSS vulnerability with certain configurations of rails-html-sanitizer"
}