CVE-2024-28199.yml

---
gem: phlex
cve: 2024-28199
ghsa: 242p-4v39-2v8g
url: https://github.com/phlex-ruby/phlex/security/advisories/GHSA-242p-4v39-2v8g
title: Cross-site Scripting (XSS) possible with maliciously
  formed HTML attribute names and values in Phlex
date: 2024-03-12
description: |
  There is a potential cross-site scripting (XSS) vulnerability that
  can be exploited via maliciously crafted user data. This was due
  to improper case-sensitivity in the code that was meant to prevent
  these attacks.

  ### Impact

  If you render an `<a>` tag with an `href` attribute set to a
  user-provided link, that link could potentially execute JavaScript
  when clicked by another user.

  ```ruby
  a(href: user_profile) { "Profile" }
  ```

  If you splat user-provided attributes when rendering any HTML or
  SVG tag, malicious event attributes could be included in the output,
  executing JavaScript when the events are triggered by another user.

  ```ruby
  h1(**JSON.parse(user_attributes))
  ```

  ### Patches

  Patches are [available on RubyGems](https://rubygems.org/gems/phlex)
  for all `1.x` minor versions. The patched versions are:

  - [1.9.1](https://rubygems.org/gems/phlex/versions/1.9.1)
  - [1.8.2](https://rubygems.org/gems/phlex/versions/1.8.2)
  - [1.7.1](https://rubygems.org/gems/phlex/versions/1.7.1)
  - [1.6.2](https://rubygems.org/gems/phlex/versions/1.6.2)
  - [1.5.2](https://rubygems.org/gems/phlex/versions/1.5.2)
  - [1.4.1](https://rubygems.org/gems/phlex/versions/1.4.1)
  - [1.3.3](https://rubygems.org/gems/phlex/versions/1.3.3)
  - [1.2.2](https://rubygems.org/gems/phlex/versions/1.2.2)
  - [1.1.1](https://rubygems.org/gems/phlex/versions/1.1.1)
  - [1.0.1](https://rubygems.org/gems/phlex/versions/1.0.1)

  If you are on `main`, it has been patched since
  [`aa50c60`](https://github.com/phlex-ruby/phlex/commit/aa50c604cdee1d0ce7ef068a4c66cbd5d43f96a1)

  ### Workarounds

  Configuring a [Content Security Policy](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy)
  that does not allow [`unsafe-inline`](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy#unsafe-inline)
  would effectively prevent this vulnerability from being exploited.

  ### References

  In addition to upgrading to a patched version of Phlex, we strongly
  recommend configuring a Content Security Policy header that does not
  allow `unsafe-inline`. Here’s how you can configure a Content Security
  Policy header in Rails.
  https://guides.rubyonrails.org/security.html#content-security-policy-header

cvss_v3: 7.1
patched_versions:
  - "~> 1.0.1"
  - "~> 1.1.1"
  - "~> 1.2.2"
  - "~> 1.3.3"
  - "~> 1.4.1"
  - "~> 1.5.2"
  - "~> 1.6.2"
  - "~> 1.7.1"
  - "~> 1.8.2"
  - ">= 1.9.1"
related:
  url:
    - https://nvd.nist.gov/vuln/detail/CVE-2024-28199
    - https://github.com/phlex-ruby/phlex/security/advisories/GHSA-242p-4v39-2v8g
    - https://github.com/phlex-ruby/phlex/commit/aa50c604cdee1d0ce7ef068a4c66cbd5d43f96a1
    - https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy
    - https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy#unsafe-inline
    - https://github.com/advisories/GHSA-242p-4v39-2v8g