Craft CMS's Missing Volume Permission Check in AssetsController::actionShowInFolder Allows Information Disclosure
Impact
AssetsController::actionShowInFolder() fetches an asset by ID and returns its filename and complete folder hierarchy (including volume handle, volume UID, folder names, folder UIDs, and folder URI paths) without checking whether the requesting user has viewAssets or viewPeerAssets permission on the asset’s volume. Any authenticated CP user — even one with zero volume permissions — can enumerate asset filenames and the full folder structure of any volume by supplying arbitrary asset IDs.
Source excerpt · OSVAffected packages
Start with the recorded fix for your release branch. Check your installed version and test compatibility before upgrading. Fixing this advisory does not rule out other vulnerabilities in the release.
| Affected range | Recorded fix |
|---|---|
| From 5.0.0-RC1 before 5.9.18Ecosystem versions | 5.9.18 |
Version evidence: OSV · GHSA-33m5-hqp9-97pw
View original version evidence (165 explicit versions)
Original source description
Summary
AssetsController::actionShowInFolder() fetches an asset by ID and returns its filename and complete folder hierarchy (including volume handle, volume UID, folder names, folder UIDs, and folder URI paths) without checking whether the requesting user has viewAssets or viewPeerAssets permission on the asset’s volume. Any authenticated CP user — even one with zero volume permissions — can enumerate asset filenames and the full folder structure of any volume by supplying arbitrary asset IDs.
This follows the exact same incomplete-patch pattern as four GHSAs merged on 2026-02-25 (GHSA-x76w-8c62-48mg, GHSA-vgjg-248p-rfm2, GHSA-5pgf-h923-m958, GHSA-3pvf-vxrv-hh9c), all of which added requireVolumePermissionByAsset() + requirePeerVolumePermissionByAsset() to sibling AssetsController actions. The actionShowInFolder method was introduced thirteen days before the patch wave and was not included in it.
Details
The vulnerability is in src/controllers/AssetsController.php at line 1437. The method:
- Calls
requireCpRequest()— verifies the request targets the CP, enforcesaccessCppermission viaController::_enforceAllowAnonymous(), but does NOT enforce any volume-level permission. - Fetches any asset by ID with
Asset::findOne($assetId)— noeditable/savablescope filter, so all assets across all volumes are reachable. - Returns sensitive structural data via JSON.
Impact
- Any authenticated control panel user with only
accessCppermission can discover the filenames and complete folder structure (names, UIDs, handles, URIs) of assets in volumes they are not authorized to access. - Sensitive volume structures — private document repositories, confidential media, internal file names — are exposed to any user who can log into the control panel.
- This enables targeted follow-up attacks: an attacker who knows a private asset’s filename and folder path may have other avenues to exfiltrate the actual file.
Resources
https://github.com/craftcms/cms/commit/e3f3eaab3d85badd713cfc2c24e5f0792ecdb586