GHSA-4wj4-79rr-pvff: Duplicate Advisory Grav: Stored CSS Injection Vulnerability

MODERATE
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CVSS 4.8
CWE-79
Published
Advisory Summary

GHSA-4wj4-79rr-pvff is a MODERATE (CVSS 4.8) grav: stored css injection vulnerability (CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) affecting Duplicate Advisory libraries in the Packagist ecosystem. The issue involves grav: stored css injection via markdown image resize() bypasses prior media style sanitizers in grav. Remediation is available in the latest vendor maintenance releases.

GHSA-4wj4-79rr-pvff at a Glance

CVE Identifier N/A
GHSA Identifier GHSA-4wj4-79rr-pvff
Severity MODERATE
CVSS v3.1 Base Score 4.8
CWE Classification CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Product Duplicate Advisory
Package Ecosystem Packagist
Published Date
Last Updated

Security Impact

CVSS: 4.8

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required High (PR:H)
User Interaction Required (UI:R)
Scope Changed (S:C)
Confidentiality Low (C:L)
Integrity Low (I:L)
Availability None (A:N)

How to Fix GHSA-4wj4-79rr-pvff

To remediate this vulnerability, upgrade all affected Duplicate Advisory dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

getgrav/grav fixed: Latest secure release 
Upgrade getgrav/grav to Latest secure release
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for getgrav/grav

How to Check if You Are Affected

To determine whether your application is affected by GHSA-4wj4-79rr-pvff, inspect your project dependencies for Duplicate Advisory:

inspect dependencies for getgrav/grav

Analyze the terminal output to locate any version of Duplicate Advisory in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'), where the product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. In Duplicate Advisory, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### 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.

GHSA-4wj4-79rr-pvff Affected Duplicate Advisory Versions

1 component(s)
Product / Package Ecosystem Affected Versions Fixed Version
getgrav/grav
 Packagist
2.0.0-rc.9
All 1 versions
2.0.0-rc.9
None specified

References

GitHub Advisory / Wiki ADVISORY
https://github.com/getgrav/grav/security/advisories/GHSA-ffmg-hfvg-jhg9
NVD — GHSA-4wj4-79rr-pvff NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-58657
Security Fix Commit FIX COMMIT
https://github.com/getgrav/grav/commit/6582166173bb8eb5869d96aea384e0e73777c94c
Security Fix Commit FIX COMMIT
https://github.com/getgrav/grav/commit/e03d29aa0d3ece16d73c1ffccfa78df8bf5f28b8
www.vulncheck.com/advisories/grav-sto... WEB
https://www.vulncheck.com/advisories/grav-stored-css-injection-via-markdown-image-resize-action

Frequently Asked Questions

What is GHSA-4wj4-79rr-pvff?
GHSA-4wj4-79rr-pvff is a security vulnerability in Duplicate Advisory involving Grav: Stored CSS injection via Markdown image resize() bypasses prior media style sanitizers in Grav under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting').
Which Duplicate Advisory versions are affected?
Affected versions include releases prior to current release patches across affected packages: getgrav/grav.
What version fixes GHSA-4wj4-79rr-pvff?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
Is getgrav/grav affected?
Yes, getgrav/grav is affected in releases prior to Latest secure release. Upgrade your dependency to Latest secure release or later.
What is the CVSS score of GHSA-4wj4-79rr-pvff?
GHSA-4wj4-79rr-pvff has a CVSS v3.1 base score of 4.8 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N.
What CWE is associated with GHSA-4wj4-79rr-pvff?
GHSA-4wj4-79rr-pvff is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') (The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.).
How can I check Packagist dependencies for GHSA-4wj4-79rr-pvff?
Run the dependency tree command: 'inspect dependencies for getgrav/grav'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-4wj4-79rr-pvff",
  "modified" : "2026-09-16T22:14:37Z",
  "published" : "2026-07-08T15:32:01Z",
  "withdrawn" : "2026-09-16T22:14:36Z",
  "aliases" : [ ],
  "summary" : "Duplicate Advisory: Grav: Stored CSS injection via Markdown image resize() bypasses prior media style sanitizers in Grav",
  "details" : "### Duplicate Advisory\nThis advisory has been withdrawn because it is a duplicate of GHSA-ffmg-hfvg-jhg9. This link is maintained to preserve external references.\n\n### Original Description\nGrav 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.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "getgrav/grav"
    },
    "versions" : [ "2.0.0-rc.9" ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/getgrav/grav/security/advisories/GHSA-ffmg-hfvg-jhg9"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-58657"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/getgrav/grav/commit/6582166173bb8eb5869d96aea384e0e73777c94c"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/getgrav/grav/commit/e03d29aa0d3ece16d73c1ffccfa78df8bf5f28b8"
  }, {
    "type" : "WEB",
    "url" : "https://www.vulncheck.com/advisories/grav-stored-css-injection-via-markdown-image-resize-action"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-09-16T22:14:36Z",
    "nvd_published_at" : "2026-07-08T14:17:20Z"
  }
}