EasyAdmin: Stored Cross-Site Scripting (XSS) via uploaded files served inline in FileField and ImageField

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.6 · CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N

EPSS

• CVE-2026-54087: 0.40% estimated exploitation activity in the next 30 days; percentile 34.68 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

EasyAdmin's FileField and ImageField accept browser-executable file types by default (FileField applies no MIME/extension restrictions; ImageField's default Image constraint accepts SVG). When the upload directory is configured inside the public web root — as shown in the documentation — EasyAdmin links to the stored file inline (no download attribute or Content-Disposition: attachment). An attacker with access to a form using these fields can upload an .html (FileField) or .svg (ImageField) file containing JavaScript. When another user opens it from the backend, it is served from the same origin and the script executes in the context of their authenticated admin session, enabling session/CSRF-token theft or privilege escalation. Exploitation requires the developer to store uploads in the public directory and a privilege gap between the uploading user and the viewing administrator. This is stored XSS only — it does not allow remote code execution, because uploaded filenames are…

Published by the source

14 Jul 2026, 19:51 UTC

Last modified by the source

14 Jul 2026, 19:51 UTC

Source last checked

26 Oct 2026, 14:50 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-8559-gwj3-q37r

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# Patch Next advisory brief: CVE-2026-54087

Advisory: EasyAdmin: Stored Cross-Site Scripting (XSS) via uploaded files served inline in FileField and ImageField
IDs: CVE-2026-54087, GHSA-8559-gwj3-q37r
Record: https://patchnext.com/advisories/cve-2026-54087 (revision 1, source checked 26 Oct 2026, 14:50 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.6)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: easycorp/easyadmin-bundle 5.0.13. A vendor fix does not mean a deployment is fixed.

## Affected components
- Packagist easycorp/easyadmin-bundle: affected >= 5.0.0, < 5.0.13; fixed in 5.0.13

## Suggested inspection (read-only)
- Packagist easycorp/easyadmin-bundle: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on easycorp/easyadmin-bundle.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-8559-gwj3-q37r (GitHub-reviewed advisory GHSA-8559-gwj3-q37r lists affected ranges: Packagist easycorp/easyadmin-bundle >=5.0.0 <5.0.13)

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