CVE-2026-41240

MEDIUM
MEDIUM Priority: 0.02 BB Relevance: 62/100
Published: 2026-04-23 Modified: 2026-10-26 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth Integ. Impact

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: Passive
S: X
AT: Present
VC: None
VI: High
VA: None

Description

DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Versions prior to 3.4.0 have an inconsistency between FORBID_TAGS and FORBID_ATTR handling when function-based ADD_TAGS is used. Commit c361baa added an early exit for FORBID_ATTR at line 1214. The same fix was not applied to FORBID_TAGS. At line 1118-1123, when EXTRA_ELEMENT_HANDLING.tagCheck returns true, the short-circuit evaluation skips the FORBID_TAGS check entirely. This allows forbidden elements to survive sanitization with their attributes intact. Version 3.4.0 patches the issue.

Weakness Classification (2)

Affected Software (1)

VendorProductVersion
cure53 dompurify < 3.4.0

Bug Bounty Relevance

62 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity

CVSS Score

6.0 / 10.0 v4.0
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS — Exploitation Probability

0.31%
Raw Score 0.003130
Percentile 24.2%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00313
2026-10-28
0.00313

Intelligence Sources

nvd ref →