CVE-2026-85600

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 v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.3 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

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-96xm-c5hr-59rx
https://www.vulncheck.com/advisories/grav-admin-before-2.0.21-stored-xss-via-username
https://github.com/getgrav/grav/security/advisories/GHSA-96xm-c5hr-59rx

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-04 12:17

Updated : 2026-09-08 20:05

NVD link : CVE-2026-85600

Mitre link : CVE-2026-85600

CVE.ORG link : CVE-2026-85600

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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