Possible XSS vulnerability with certain configurations of rails-html-sanitizer

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.1 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

EPSS

• CVE-2022-23519: 1.05% estimated exploitation activity in the next 30 days; percentile 64.46 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

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: see https://guides.rubyonrails.org/configuring.html#configuring-action-view 2. using a :tags option to the Action View helper sanitize: see https://api.rubyonrails.org/classes/ActionView/Helpers/SanitizeHelper.html#method-i-sanitize 3. using Rails::Html::SafeListSanitizer class method allowedtags=: 4. using a :tags options to the…

Published by the source

13 Dec 2022, 17:50 UTC

Last modified by the source

4 Nov 2025, 16:42 UTC

Source last checked

26 Oct 2026, 15:51 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-9h9g-93gc-623h

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2022-23519

Advisory: Possible XSS vulnerability with certain configurations of rails-html-sanitizer
IDs: CVE-2022-23519, GHSA-9h9g-93gc-623h
Record: https://patchnext.com/advisories/cve-2022-23519 (revision 1, source checked 26 Oct 2026, 15:51 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: rails-html-sanitizer 1.4.4. A vendor fix does not mean a deployment is fixed.

## Affected components
- RubyGems rails-html-sanitizer: affected < 1.4.4; fixed in 1.4.4

## Suggested inspection (read-only)
- RubyGems rails-html-sanitizer: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on rails-html-sanitizer.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-9h9g-93gc-623h (GitHub-reviewed advisory GHSA-9h9g-93gc-623h lists affected ranges: RubyGems rails-html-sanitizer >=0 <1.4.4)

Commands are suggestions: review each one before running it.