Grav Admin before 2.0.21 Stored XSS via username (CVE-2026-85600) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-85600

Grav Admin before 2.0.21 Stored XSS via username

Answer in brief

CVE-2026-85600 records a Unknown severity vulnerability in Grav Admin before 2.0.21 Stored XSS via username. The current sources do not mark it as known exploited. The current feed maps getgrav/grav (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 4, 2026Updated Sep 4, 2026Source checked Sep 4, 2026First seen by HOL Sep 4, 2026Material review Sep 4, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps getgrav/grav (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
getgrav/gravgeneric	>=0 <2.0.21	2.0.21

Recommended response

Check inventory. Check lockfiles and deployed manifests for getgrav/grav.
Review the reported fix. Update getgrav/grav to 2.0.21 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 4, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 4, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 4, 2026

Sources and claim methodology

Upstream source 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.

Quoted source text, attributed separately from HOL analysis.