CVE-2026-44737: Grav Cross-Site Scripting Vulnerability

MODERATE
Advisory Identifier: GHSA-fmg2-f5r9-24qc
CWE-79
Published
Advisory Summary

CVE-2026-44737 is a MODERATE cross-site scripting vulnerability (CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) affecting Grav libraries in the Packagist ecosystem. The issue involves stored xss via page title (data[header][title]) in admin panel. Remediation is available by upgrading affected packages to version 1.7.49.5.

CVE-2026-44737 at a Glance

CVE Identifier CVE-2026-44737
GHSA Identifier GHSA-fmg2-f5r9-24qc
Severity MODERATE
CVSS v3.1 Base Score N/A
CWE Classification CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Product Grav
Package Ecosystem Packagist
Published Date
Last Updated

How to Fix CVE-2026-44737

To remediate this vulnerability, upgrade all affected Grav 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: 1.7.49.5
Upgrade getgrav/grav to 1.7.49.5
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 CVE-2026-44737, inspect your project dependencies for Grav:

inspect dependencies for getgrav/grav

Analyze the terminal output to locate any version of Grav in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.7.49.5), 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 Grav, 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

### Summary _A Stored Cross-Site Scripting (XSS) vulnerability was identified in the /admin/pages/[page] endpoint of the Grav application. This vulnerability allows attackers to inject malicious scripts into the data[header][title] parameter._ --- ### Details Vulnerable Endpoint: GET /admin/pages/[page] Parameter: data[header][title] The application fails to properly validate and sanitize user input in the data[header][title] parameter. As a result, attackers can craft a malicious URL with an XSS payload. When this URL is accessed, the injected script is reflected back in the HTTP response and executed within the context of the victim's browser session. --- ### PoC **Payload:** `<img src=1 onerror=alert(1)>` 1. Log in to the Grav Admin Panel and navigate to Pages. 2. Create a new page or edit an existing one. 3. Edit title of the page to `<img src=1 onerror=alert(1)>` <img width="1897" height="700" alt="image" src="https://github.com/user-attachments/assets/77a129ca-5c2b-4743-8c56-c17fa456eefa" /> 4. Save page 5. Open the move function and click on the folder having the payload <img width="1904" height="984" alt="image" src="https://github.com/user-attachments/assets/44f8f88f-76c4-449f-8c4e-11e8e2c51d8f" /> <img width="1902" height="995" alt="image" src="https://github.com/user-attachments/assets/1dc2ef15-e534-4e87-93ea-92bc573af7f1" /> --- ### Impact Stored cross-site scripting (XSS) attacks can have serious consequences, including: - User actions: Attackers can perform actions on behalf of the user - Data theft: Sensitive information such as session cookies can be stolen - Account compromise: Attackers may impersonate legitimate users - Malicious code execution: Arbitrary JavaScript code can run in the user’s browser - Website defacement or misinformation: Malicious output may be injected visually - User redirection: Victims may be redirected to phishing or malicious websites By [Vu Duc Hieu](https://github.com/vdh1612) Contributor [Simon Tran](https://github.com/simontranduy)

CVE-2026-44737 Affected Grav Versions

1 component(s)
Fixed Versions:
1.7.49.5
Product / Package Ecosystem Affected Versions Fixed Version
getgrav/grav
Packagist
< 1.7.49.5
1.7.49.5

References

Frequently Asked Questions

What is CVE-2026-44737?
CVE-2026-44737 is a security vulnerability in Grav involving Stored XSS via page title (data[header][title]) in admin panel under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting').
Which Grav versions are affected?
Affected versions include releases prior to 1.7.49.5 across affected packages: getgrav/grav.
What version fixes CVE-2026-44737?
Upgrading to 1.7.49.5 (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 1.7.49.5. Upgrade your dependency to 1.7.49.5 or later.
What CWE is associated with CVE-2026-44737?
CVE-2026-44737 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 CVE-2026-44737?
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
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-fmg2-f5r9-24qc",
  "modified" : "2026-05-13T14:04:40Z",
  "published" : "2026-05-08T19:38:00Z",
  "aliases" : [ "CVE-2026-44737" ],
  "summary" : "Grav: Stored XSS via page title (data[header][title]) in admin panel",
  "details" : "### Summary\n_A Stored Cross-Site Scripting (XSS) vulnerability was identified in the /admin/pages/[page] endpoint of the Grav application. This vulnerability allows attackers to inject malicious scripts into the data[header][title] parameter._\n\n--- \n\n### Details\nVulnerable Endpoint: GET /admin/pages/[page]\nParameter: data[header][title]\n\nThe application fails to properly validate and sanitize user input in the data[header][title] parameter. As a result, attackers can craft a malicious URL with an XSS payload. When this URL is accessed, the injected script is reflected back in the HTTP response and executed within the context of the victim's browser session.\n\n--- \n\n### PoC\n**Payload:** `<img src=1 onerror=alert(1)>`\n\n1. Log in to the Grav Admin Panel and navigate to Pages.\n \n2. Create a new page or edit an existing one.\n\n3. Edit title of the page to  `<img src=1 onerror=alert(1)>`\n\n<img width=\"1897\" height=\"700\" alt=\"image\" src=\"https://github.com/user-attachments/assets/77a129ca-5c2b-4743-8c56-c17fa456eefa\" />\n\n4. Save page\n \n5. Open the move function and click on the folder having the payload\n\n<img width=\"1904\" height=\"984\" alt=\"image\" src=\"https://github.com/user-attachments/assets/44f8f88f-76c4-449f-8c4e-11e8e2c51d8f\" />\n\n<img width=\"1902\" height=\"995\" alt=\"image\" src=\"https://github.com/user-attachments/assets/1dc2ef15-e534-4e87-93ea-92bc573af7f1\" />\n\n--- \n\n### Impact\n\nStored cross-site scripting (XSS) attacks can have serious consequences, including:\n\n- User actions: Attackers can perform actions on behalf of the user\n\n- Data theft: Sensitive information such as session cookies can be stolen\n\n- Account compromise: Attackers may impersonate legitimate users\n\n- Malicious code execution: Arbitrary JavaScript code can run in the user’s browser\n\n- Website defacement or misinformation: Malicious output may be injected visually\n\n- User redirection: Victims may be redirected to phishing or malicious websites\n\nBy [Vu Duc Hieu](https://github.com/vdh1612) \nContributor [Simon Tran](https://github.com/simontranduy)",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:L/VI:L/VA:N/SC:H/SI:H/SA:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "getgrav/grav"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.7.49.5"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/getgrav/grav/security/advisories/GHSA-fmg2-f5r9-24qc"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-44737"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/getgrav/grav-plugin-admin/commit/f67cc18e81d8767bb43d29ee6422c55ed0427803"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/getgrav/grav"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-08T19:38:00Z",
    "nvd_published_at" : "2026-05-11T17:16:34Z"
  }
}