Description (CNA)
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 <img src=1 onerror=alert(1)>, executing arbitrary JavaScript in visitors' browsers.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| getgrav / grav | affected 0 before 2.0.1; unaffected 2.0.1 |
CWE
CWE-79
References
- https://github.com/getgrav/grav/security/advisories/GHSA-2c4f-86xc-cr74
- https://www.vulncheck.com/advisories/grav-before-xss-via-twig-string-concatenation
ADP enrichment
No English description supplied.