---
id: GHSA-4wj4-79rr-pvff
title: >-
  Duplicate Advisory: Grav: Stored CSS injection via Markdown image resize()
  bypasses prior media style sanitizers in Grav
summary: >-
  Duplicate Advisory: Grav: Stored CSS injection via Markdown image resize()
  bypasses prior media style sanitizers in Grav
severity: medium
cvss: 4.8
cwe:
  - CWE-79
vendor: getgrav
product: getgrav/grav
ecosystem: composer
affected:
  - getgrav/grav = 2.0.0-rc.9
published: '2026-07-08'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T22:14:38Z'
source: GHSA
sourceUrl: 'https://github.com/advisories/GHSA-4wj4-79rr-pvff'
references:
  - url: 'https://github.com/getgrav/grav/security/advisories/GHSA-ffmg-hfvg-jhg9'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-58657'
  - url: >-
      https://github.com/getgrav/grav/commit/6582166173bb8eb5869d96aea384e0e73777c94c
  - url: >-
      https://github.com/getgrav/grav/commit/e03d29aa0d3ece16d73c1ffccfa78df8bf5f28b8
  - url: >-
      https://www.vulncheck.com/advisories/grav-stored-css-injection-via-markdown-image-resize-action
  - url: 'https://github.com/advisories/GHSA-4wj4-79rr-pvff'
tags:
  - ghsa
  - composer
ingestedAt: '2026-09-16T23:07:58.094Z'
---

## Overview

### Duplicate Advisory
This advisory has been withdrawn because it is a duplicate of GHSA-ffmg-hfvg-jhg9. This link is maintained to preserve external references.

### Original Description
Grav before 2.0.0 (affected through 2.0.0-rc.9 and the 2.0 branch) contains a stored CSS injection vulnerability in the Markdown image resize() media action. Prior media hardening rejects direct ?style= payloads and unsafe attribute() fallbacks, but the resize() action in Excerpts::processMediaActions() writes caller-controlled values directly into the image's styleAttributes. A lower-privileged content editor who can edit page Markdown can store a crafted image URL with semicolon-delimited CSS declarations in the resize parameters, which are rendered into the final <img style=...> attribute when a higher-privileged reviewer/admin views the page or preview. This does not require JavaScript execution but enables UI redress/overlay and content-manipulation attacks (e.g., a full-viewport fixed overlay). Fixed in 2.0.0.

## Affected packages

- `getgrav/grav = 2.0.0-rc.9`

## Remediation

Refer to the advisory for the patched release.