CVE-2026-86197

Grav before 2.0.20 contains a cross-site scripting vulnerability in the Twig sandbox policy that allowlists addJs and addCss methods on Grav\Common\Assets without proper output escaping. Page editors can inject arbitrary script by registering malicious assets or injecting attributes, which are rendered unescaped into document head tags and executed for all visitors including administrators.

CVSS 4.0

5.1CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

EPSS

0.4% chance of exploitation in the next 30 days; higher than 35% of CVEs (scores of 2026-10-25)

CWE

CWE-79

Published

2026-09-05

Modified

2026-10-08

Record from

the NVD, synced 2026-10-19

References

• https://github.com/getgrav/grav/security/advisories/GHSA-8hgv-xc77-jmcr
• https://www.vulncheck.com/advisories/grav-before-2.0.20-cross-site-scripting-via-assets-sandbox

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