CVE-2026-61453

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.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/getgrav/grav/security/advisories/GHSA-2c4f-86xc-cr74
https://www.vulncheck.com/advisories/grav-before-xss-via-twig-string-concatenation
https://github.com/getgrav/grav/security/advisories/GHSA-2c4f-86xc-cr74

Configurations

No configuration.

History

15 Jul 2026, 19:18

Type	Values Removed	Values Added
References	~~() https://github.com/getgrav/grav/security/advisories/GHSA-2c4f-86xc-cr74 -~~	() https://github.com/getgrav/grav/security/advisories/GHSA-2c4f-86xc-cr74 -

15 Jul 2026, 12:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-15 12:18

Updated : 2026-07-15 19:50

NVD link : CVE-2026-61453

Mitre link : CVE-2026-61453

CVE.ORG link : CVE-2026-61453

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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