Loofah is a general library for manipulating and transforming HTML/XML documents and fragments, built on top of Nokogiri. Prior to 2.25.3, the Loofah HTML5 sanitizer checks href and xlink:href on elements in SVG_ALLOW_LOCAL_HREF with a regular expression whose line anchor and newline-matching whitespace cause an all-whitespace value to be rescanned from every line start. An attacker can submit an SVG reference element with a long multiline-whitespace attribute and consume CPU quadratically during sanitization. CRuby 3.1 and earlier and JRuby are affected, while CRuby 3.2 and later uses linear-time regular-expression matching. The default safelist reaches the vulnerable check without a configuration change. This issue is fixed in version 2.25.3.
Advisories
| Source | ID | Title |
|---|---|---|
Github GHSA |
GHSA-mf2j-8f84-cc9q | Loofah: Regular expression denial of service in the SVG local-reference check |
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Fri, 13 Nov 2026 01:15:00 +0000
| Type | Values Removed | Values Added |
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| First Time appeared |
Flavorjones
Flavorjones loofah |
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| Vendors & Products |
Flavorjones
Flavorjones loofah |
Thu, 12 Nov 2026 20:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Loofah is a general library for manipulating and transforming HTML/XML documents and fragments, built on top of Nokogiri. Prior to 2.25.3, the Loofah HTML5 sanitizer checks href and xlink:href on elements in SVG_ALLOW_LOCAL_HREF with a regular expression whose line anchor and newline-matching whitespace cause an all-whitespace value to be rescanned from every line start. An attacker can submit an SVG reference element with a long multiline-whitespace attribute and consume CPU quadratically during sanitization. CRuby 3.1 and earlier and JRuby are affected, while CRuby 3.2 and later uses linear-time regular-expression matching. The default safelist reaches the vulnerable check without a configuration change. This issue is fixed in version 2.25.3. | |
| Title | Loofah: Regular expression denial of service in the SVG local-reference check | |
| Weaknesses | CWE-1333 CWE-400 |
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| References |
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| Metrics |
cvssV3_1
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Projects
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Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2026-11-12T20:41:25.574Z
Reserved: 2026-11-10T20:07:44.958Z
Link: CVE-2026-126205
No data.
Status : Awaiting Analysis
Published: 2026-11-12T21:17:21.487
Modified: 2026-11-12T22:09:39.233
Link: CVE-2026-126205
No data.
OpenCVE Enrichment
Updated: 2026-11-13T15:30:03Z
Github GHSA