Grav: Stored CSS injection via Markdown image ?style=… reaches MediaObjectTrait::style() (CVE-2026-55890) | HOL Guard CVE

Medium · CVSS 4.8CVE-2026-55890GHSA-PMF8-G7C8-7V54

Grav: Stored CSS injection via Markdown image ?style=… reaches MediaObjectTrait::style()

Answer in brief

CVE-2026-55890 records a Medium severity (CVSS 4.8) vulnerability in Grav: Stored CSS injection via Markdown image ?style=… reaches MediaObjectTrait::style(). The current sources do not mark it as known exploited. The current feed maps getgrav/grav (composer), 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 Jul 10, 2026Updated Jul 10, 2026Source checked Sep 17, 2026First seen by HOL Jun 19, 2026Material review Jul 10, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 4.8
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 4.8. 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 (composer), getgrav/grav (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
getgrav/gravcomposer	<=2.0.0-rc.8	2.0.0-rc.9
getgrav/gravgeneric	< 2.0.0-rc.9	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for getgrav/grav, getgrav/grav.
Review the reported fix. Update getgrav/grav to 2.0.0-rc.9 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Jul 10, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Jul 10, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Jun 19, 2026

Sources and claim methodology

Upstream source description

Grav is a file-based Web platform. Prior to 2.0.0-rc.9, Grav's incomplete fix for stored XSS through the Markdown media attribute action (CVE-2026-42841) leaves the sibling MediaObjectTrait::style method reachable through the same Markdown excerpt-action pipeline, allowing an editor to save Markdown image style parameters that are written into the rendered img style attribute without sanitization. This issue is fixed in version 2.0.0-rc.9.

Quoted source text, attributed separately from HOL analysis.