CVE-2026-61453
Severity CVSS v4.0:
MEDIUM
Type:
CWE-79
Cross-Site Scripting (XSS)
Publication date:
15/07/2026
Last modified:
15/07/2026
Description
Grav v2.0.0 contains a cross-site scripting vulnerability (fixed in 2.0.1). The XSS blueprint validator (Security::detectXss()) runs on raw page content before Twig processing. When Twig content processing is enabled (twig_content.process_enabled: true), an attacker with page-write API permission can use Twig's string concatenation operator (~) to dynamically construct event handler names, dangerous tag names, or dangerous protocols at render time (e.g. {% set x = "on" ~ "error" %}). The validator sees only the harmless Twig expression and allows the content, but after Twig rendering the output (rendered via {{ page.content|raw }}) contains an active payload such as , executing arbitrary JavaScript in visitors' browsers.
Impact
Base Score 4.0
5.10
Severity 4.0
MEDIUM
Base Score 3.x
6.10
Severity 3.x
MEDIUM