Vulnerability Description
Grav Admin (getgrav/grav-plugin-admin2) versions <= 2.0.19 contain a stored cross-site scripting vulnerability in the tHtml() function (src/lib/stores/i18n.svelte.ts), which substitutes untrusted parameters such as usernames into translation templates before parsing the result as markdown. Grav's server-side username validation (DataUser::isValidUsername) blocks filesystem-dangerous characters but not <, >, ", or ', allowing an attacker to register a username containing an HTML payload. When an administrator views a UI surface that renders the username through tHtml()—such as the two-factor force-disable confirmation prompt or the 'page is locked' editor notice—the payload executes in their authenticated session. Fixed in 2.0.21.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/getgrav/grav/security/advisories/GHSA-96xm-c5hr-59rx
- https://www.vulncheck.com/advisories/grav-admin-before-2.0.21-stored-xss-via-use
- https://github.com/getgrav/grav/security/advisories/GHSA-96xm-c5hr-59rx
FAQ
What is CVE-2026-85600?
CVE-2026-85600 is a vulnerability with a CVSS score of 5.4 (MEDIUM). Grav Admin (getgrav/grav-plugin-admin2) versions <= 2.0.19 contain a stored cross-site scripting vulnerability in the tHtml() function (src/lib/stores/i18n.svelte.ts), which substitutes untrusted para...
How severe is CVE-2026-85600?
CVE-2026-85600 has been rated MEDIUM with a CVSS base score of 5.4/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-85600?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.