The Grav Email plugin (getgrav/grav-plugin-email) before 4.2.2 renders page-editor-controlled Email action parameters as unsandboxed Twig templates. An authenticated remote user with only api.access and api.pages.write permissions can place a Twig expression in header.form.process.email.body, publish the page, and submit the form to execute an arbitrary operating-system command as the account running PHP.
https://www.vulncheck.com/advisories/grav-before-remote-code-execution-via-email-twig
https://github.com/getgrav/grav/security/advisories/GHSA-gh8j-q67c-j53f
Published: 2026-08-25
Updated: 2026-08-27
Base Score: 9
Vector: CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:C
Severity: High
Base Score: 8.8
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity: High
Base Score: 8.7
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Severity: High
EPSS: 0.00364