CVE-2026-40301 | rhukster/dom-sanitizer: SVG <style> tag allows CSS injection via unfiltered url() and @import directives

DOMSanitizer is a DOM/SVG/MathML Sanitizer for PHP 7.3+. Prior to version 1.0.10, DOMSanitizer::sanitize() allows <style> elements in SVG content but never inspects their text content. CSS url() references and @import rules pass through unfiltered, causing the browser to issue HTTP requests to attacker-controlled hosts when the sanitized SVG is rendered. Version 1.0.10 fixes the issue.

Published: 2026-04-17 Last update: 2026-04-29 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-40301 is rated Low Risk (21.6/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.03%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-40301

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-18 0.03%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-40301

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.7 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
2.8 1.4 [email protected]

Weakness enumeration for CVE-2026-40301

GitHub Security Advisory for CVE-2026-40301

GHSA-93vf-569f-22cq · Severity: medium · Ecosystem: composer — rhukster/dom-sanitizer: SVG <style> tag allows CSS injection via unfiltered url() and @import directives

Affected software / configurations for CVE-2026-40301

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-40301

cvelogic Threat Intelligence