CVE-2024-32970: Phlex Cross-Site Scripting Vulnerability

HIGH
Advisory Identifier: GHSA-9p57-h987-4vgx
CVSS 7.1
CWE-79
Published
Advisory Summary

CVE-2024-32970 is a HIGH (CVSS 7.1) cross-site scripting vulnerability (CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) affecting Phlex libraries in the RubyGems ecosystem. The issue involves phlex vulnerable to cross-site scripting (xss) via maliciously formed html attribute names and values. Remediation is available by upgrading affected packages to version 1.9.3, 1.10.2.

CVE-2024-32970 at a Glance

CVE Identifier CVE-2024-32970
GHSA Identifier GHSA-9p57-h987-4vgx
Severity HIGH
CVSS v3.1 Base Score 7.1
CWE Classification CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Product Phlex
Package Ecosystem RubyGems
Published Date
Last Updated

Security Impact

CVSS: 7.1

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction Required (UI:R)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity Low (I:L)
Availability None (A:N)

How to Fix CVE-2024-32970

To remediate this vulnerability, upgrade all affected Phlex dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

phlex fixed: 1.9.3
Upgrade phlex to 1.9.3
phlex fixed: 1.10.2
Upgrade phlex to 1.10.2
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

inspect dependencies for phlex

How to Check if You Are Affected

To determine whether your application is affected by CVE-2024-32970, inspect your project dependencies for Phlex:

inspect dependencies for phlex

Analyze the terminal output to locate any version of Phlex in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.9.3), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'), where the product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. In Phlex, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

There is a potential cross-site scripting (XSS) vulnerability that can be exploited via maliciously crafted user data. The reason these issues were not detected before is the escapes were working as designed. However, their design didn't take into account just how recklessly permissive browser are when it comes to executing unsafe JavaScript via HTML attributes. ### 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 minor versions released in the last year. - [1.10.2](https://rubygems.org/gems/phlex/versions/1.10.2) - [1.9.3](https://rubygems.org/gems/phlex/versions/1.9.3) If you are on `main`, it has been patched since [`da8f943`](https://github.com/phlex-ruby/phlex/commit/da8f94342a84cff9d78c98bcc3b3604ee2e577d2) ### 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

CVE-2024-32970 Affected Phlex Versions

2 component(s)
Fixed Versions:
1.9.31.10.2
Product / Package Ecosystem Affected Versions Fixed Version
phlex
RubyGems
< 1.9.3
1.9.3
phlex
RubyGems
≥ 1.10.0
< 1.10.2
1.10.2

References

Frequently Asked Questions

What is CVE-2024-32970?
CVE-2024-32970 is a security vulnerability in Phlex involving Phlex vulnerable to Cross-site Scripting (XSS) via maliciously formed HTML attribute names and values under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting').
Which Phlex versions are affected?
Affected versions include releases prior to 1.9.3, 1.10.2 across affected packages: phlex.
What version fixes CVE-2024-32970?
Upgrading to 1.9.3, 1.10.2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is phlex affected?
Yes, phlex is affected in releases prior to 1.9.3, 1.10.2. Upgrade your dependency to 1.9.3, 1.10.2 or later.
What is the CVSS score of CVE-2024-32970?
CVE-2024-32970 has a CVSS v3.1 base score of 7.1 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N.
What CWE is associated with CVE-2024-32970?
CVE-2024-32970 is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') (The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.).
How can I check RubyGems dependencies for CVE-2024-32970?
Run the dependency tree command: 'inspect dependencies for phlex'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-9p57-h987-4vgx",
  "modified" : "2024-05-03T20:17:02Z",
  "published" : "2024-05-01T16:37:21Z",
  "aliases" : [ "CVE-2024-32970" ],
  "summary" : "Phlex vulnerable to Cross-site Scripting (XSS) via maliciously formed HTML attribute names and values",
  "details" : "There is a potential cross-site scripting (XSS) vulnerability that can be exploited via maliciously crafted user data.\n\nThe reason these issues were not detected before is the escapes were working as designed. However, their design didn't take into account just how recklessly permissive browser are when it comes to executing unsafe JavaScript via HTML attributes.\n\n### Impact\n\nIf 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.\n\n```ruby\na(href: user_profile) { \"Profile\" }\n```\n\nIf 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.\n\n```ruby\nh1(**JSON.parse(user_attributes))\n```\n\n### Patches\nPatches are [available on RubyGems](https://rubygems.org/gems/phlex) for all minor versions released in the last year.\n\n- [1.10.2](https://rubygems.org/gems/phlex/versions/1.10.2)\n- [1.9.3](https://rubygems.org/gems/phlex/versions/1.9.3)\n\nIf you are on `main`, it has been patched since [`da8f943`](https://github.com/phlex-ruby/phlex/commit/da8f94342a84cff9d78c98bcc3b3604ee2e577d2)\n\n### Workarounds\nConfiguring 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.\n\n### References\n\nIn 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",
  "severity" : [ {
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        "fixed" : "1.10.2"
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    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/phlex-ruby/phlex/security/advisories/GHSA-9p57-h987-4vgx"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2024-32970"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/phlex-ruby/phlex/commit/da8f94342a84cff9d78c98bcc3b3604ee2e577d2"
  }, {
    "type" : "WEB",
    "url" : "https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy"
  }, {
    "type" : "WEB",
    "url" : "https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy#unsafe-inline"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/payloadbox/xss-payload-list"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/phlex-ruby/phlex"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/phlex/CVE-2024-32970.yml"
  }, {
    "type" : "WEB",
    "url" : "https://rubygems.org/gems/phlex"
  }, {
    "type" : "WEB",
    "url" : "https://rubygems.org/gems/phlex/versions/1.10.2"
  }, {
    "type" : "WEB",
    "url" : "https://rubygems.org/gems/phlex/versions/1.9.3"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2024-05-01T16:37:21Z",
    "nvd_published_at" : "2024-04-30T23:15:06Z"
  }
}