CVE-2026-128068

rails-html-sanitizer: Possible regular expression denial of service with certain configurations

  • Medium 5.3

Description

rails-html-sanitizer is responsible for sanitizing HTML fragments in Rails applications. From 1.0.3 through 1.7.1, Rails::HTML::PermitScrubber checks SVG href and xlink:href local references with a pattern whose line-start anchor and whitespace class cause an all-whitespace value to be rescanned from each line start. An attacker who supplies HTML can cause quadratic CPU consumption when an application customizes its allowed tags to include an SVG reference element such as use and permits href or xlink:href. The default allowed tag configuration is not affected. CRuby 3.2 and later uses linear-time regular expression matching for this pattern, while CRuby 3.1 and earlier and JRuby are affected. This issue is fixed in version 1.7.2.

Key facts

Published
13 Nov 2026
Last changed
13 Nov 2026
Assigned by
GitHub_M
EPSS
0.453% likely to be exploited in the next 30 days, higher than 39.873% of CVEs (scores for 15 Nov 2026)

Severity scores

Each score is shown as its source gave it. They are not averaged or merged.

  • 5.3CVSS 3.1, Mediumfrom the CNA (GitHub_M)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Historical context and remediation

This reference retains the original CVE publication date. A recent record update does not mean a new attack occurred.

No separately sourced impact summary is available on this page yet. Consult the description, version data and dated exploitation evidence.

No explicit remediation statement is available on this page yet. Consult the original record and vendor references before choosing a fix.

Version statuses below come from the CNA. An “unaffected” version is not necessarily a currently supported release or proof of a patch date. EPSS is a dated risk estimate, not a count of historical attacks.

Read the original CVE record.

Affected products

VendorProductVersions
railsrails-html-sanitizer
  • >= 1.0.3, < 1.7.2 (affected)

Timeline

  1. 13 Nov 2026 Published

Weakness

References