Inefficient Regular Expression Complexity in rails-html-sanitizer

Exploitation

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

CVSS

7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

• CVE-2022-23517: 1.58% estimated exploitation activity in the next 30 days; percentile 75.51 (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 Certain configurations of rails-html-sanitizer < 1.4.4 use an inefficient regular expression that is susceptible to excessive backtracking when attempting to sanitize certain SVG attributes. This may lead to a denial of service through CPU resource consumption. Mitigation Upgrade to rails-html-sanitizer = 1.4.4. Severity The maintainers have evaluated this as High Severity 7.5 (CVSS3.1). References - CWE - CWE-1333: Inefficient Regular Expression Complexity (4.9) - https://hackerone.com/reports/1684163 Credit This vulnerability was responsibly reported by @ooooooo-q (https://github.com/ooooooo-q).

Published by the source

13 Dec 2022, 17:43 UTC

Last modified by the source

4 Nov 2025, 16:41 UTC

Source last checked

26 Oct 2026, 15:51 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-5x79-w82f-gw8w

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# Patch Next advisory brief: CVE-2022-23517

Advisory: Inefficient Regular Expression Complexity in rails-html-sanitizer
IDs: CVE-2022-23517, GHSA-5x79-w82f-gw8w
Record: https://patchnext.com/advisories/cve-2022-23517 (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: High (CVSS 7.5)
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-5x79-w82f-gw8w (GitHub-reviewed advisory GHSA-5x79-w82f-gw8w lists affected ranges: RubyGems rails-html-sanitizer >=0 <1.4.4)

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