CVE-2026-126207: flavorjones loofah · Incorrect Behavior Order: Validate Before Canonicalize
Affects flavorjones loofahSource CVE Database V5
Not known to be exploited · CVSS 4.7 Medium : upgrade to 2.25.3 when convenient.
Data as of 12 Nov 2026, 22:04 UTC
Thin evidence
One scorer or none| CNA (GitHub_M) | CVSS 3.1 | 4.7 |
|---|
- Patch
- Available – fixed in 2.25.3
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:NExploitation evidence
Disclosed: evidence found.
CVE published 12 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 12 Nov 2026.
What to do
Upgrade flavorjones loofah to 2.25.3.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| flavorjonesloofah | Affected
| Fixed in
|
AI-suggested
Upgrade to loofah version 2.25.3 or later, where this issue is fixed. No additional mitigation is required as the vendor has provided an official fix.
Description
A vulnerability in flavorjones loofah versions prior to 2.25.3 allows an attacker to craft CSS that causes a viewer's browser to make unintended requests to attacker-chosen URLs. This occurs because the scrub_css method only validates the first parse of a style attribute and then rebuilds CSS with decoded identifier escapes, enabling certain CSS properties like list-style or cursor to trigger these requests. While no script execution or response reading is possible, the requests can leak the viewer's IP address, user agent, timing, and access to internal network hosts. The issue is fixed in version 2.25.3.
References
- github.com/flavorjones/loofah/security/advisories/GHSA-m3x9-938q-5767 (opens in a new tab)
- github.com/flavorjones/loofah/pull/324 (opens in a new tab)
- github.com/flavorjones/loofah/commit/b198a36e44c9c5408163ac50787825e8ca0b166b (opens in a new tab)
- github.com/flavorjones/loofah/releases/tag/v2.25.3 (opens in a new tab)