CVE-2026-55409: Filament Cross-Site Scripting Vulnerability

HIGH
Advisory Identifier: GHSA-m9cv-24rx-8mv7
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CVSS 7.6
CWE-79
Published
Advisory Summary

CVE-2026-55409 is a HIGH (CVSS 7.6) cross-site scripting vulnerability (CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) affecting Filament libraries in the Packagist ecosystem. The issue involves disabled richeditor field state can be used for xss. Remediation is available by upgrading affected packages to version 3.3.53.

CVE-2026-55409 at a Glance

CVE Identifier CVE-2026-55409
GHSA Identifier GHSA-m9cv-24rx-8mv7
Severity HIGH
CVSS v3.1 Base Score 7.6
CWE Classification CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Product Filament
Package Ecosystem Packagist
Published Date
Last Updated

Security Impact

CVSS: 7.6

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

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

How to Fix CVE-2026-55409

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

filament/forms fixed: 3.3.53 
Upgrade filament/forms to 3.3.53
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 filament/forms

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-55409, inspect your project dependencies for Filament:

inspect dependencies for filament/forms

Analyze the terminal output to locate any version of Filament in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 3.3.53), 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 Filament, 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

In Filament v3, a disabled `RichEditor` field rendered its raw state without sanitizing HTML. Where the data stored in this field's state isn't sanitized already when the form state was filled, an attacker could plant malicious HTML or JavaScript and achieve XSS that executes for users who view the form. Please note that Filament v4 and above does not use the same mechanism for rendering a disabled `RichEditor` so this advisory does not apply.

CVE-2026-55409 Affected Filament Versions

1 component(s)
Fixed Versions:
3.3.53
Product / Package Ecosystem Affected Versions Fixed Version
filament/forms
 Packagist
≥ 3.0.0
< 3.3.53
3.3.53

References

GitHub Advisory / Wiki ADVISORY
https://github.com/filamentphp/filament/security/advisories/GHSA-m9cv-24rx-8mv7
Filament Source Repository REPOSITORY
https://github.com/filamentphp/filament/pull/20029
Filament Source Repository REPOSITORY
https://github.com/filamentphp/filament
Filament Release RELEASE
https://github.com/filamentphp/filament/releases/tag/v3.3.53

Frequently Asked Questions

What is CVE-2026-55409?
CVE-2026-55409 is a security vulnerability in Filament involving Disabled RichEditor field state can be used for XSS under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting').
Which Filament versions are affected?
Affected versions include releases prior to 3.3.53 across affected packages: filament/forms.
What version fixes CVE-2026-55409?
Upgrading to 3.3.53 (or the latest patched release for your respective branch) resolves the vulnerability.
Is filament/forms affected?
Yes, filament/forms is affected in releases prior to 3.3.53. Upgrade your dependency to 3.3.53 or later.
What is the CVSS score of CVE-2026-55409?
CVE-2026-55409 has a CVSS v3.1 base score of 7.6 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N.
What CWE is associated with CVE-2026-55409?
CVE-2026-55409 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-2026-55409?
Run the dependency tree command: 'inspect dependencies for filament/forms'. 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-m9cv-24rx-8mv7",
  "modified" : "2026-06-17T18:41:12Z",
  "published" : "2026-06-17T18:41:12Z",
  "aliases" : [ "CVE-2026-55409" ],
  "summary" : "Filament: Disabled RichEditor field state can be used for XSS",
  "details" : "In Filament v3, a disabled `RichEditor` field rendered its raw state without sanitizing HTML. Where the data stored in this field's state isn't sanitized already when the form state was filled, an attacker could plant malicious HTML or JavaScript and achieve XSS that executes for users who view the form.\n\nPlease note that Filament v4 and above does not use the same mechanism for rendering a disabled `RichEditor` so this advisory does not apply.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "filament/forms"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "3.0.0"
      }, {
        "fixed" : "3.3.53"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 3.3.52"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/filamentphp/filament/security/advisories/GHSA-m9cv-24rx-8mv7"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/filamentphp/filament/pull/20029"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/filamentphp/filament"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/filamentphp/filament/releases/tag/v3.3.53"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-06-17T18:41:12Z",
    "nvd_published_at" : null
  }
}