Not scored yet

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.

What this means for your business

  • FIRST's prediction model gives it a 0.3% chance of attack attempts being seen in the next 30 days, ranking above 17% of all known flaws.

What to do

  1. 1Ask your IT team or provider whether any of your systems use the affected product.
  2. 2If you do, follow the vendor's guidance. No patch reference has been published yet.

Not sure if your company is exposed?

Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

Scoring

CVSS
Not yet scored
CVSS v4
5.1
Weakness
CWE-79
Assigned by
disclosure@vulncheck.com

Dates

Published
2026-09-05
Last modified
2026-09-10
Sources
NVD

References