GHSA-3pvf-vxrv-hh9c CVE-2026-33158
Craft CMS: Low-privilege users could read private asset contents when editing an asset (IDOR)
- Severity
- 0.0 / 10
- Medium · CVSS 4.0
- Exploit chance (EPSS)
- 0.36%
- Chance of exploitation in the next 30 days. Higher than 29.65% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-639 Authorization Bypass Through User-Controlled Key
- Fix
4.17.8- Upgrade craftcms/cms to this version or later
Description
Summary
A low-privileged authenticated user can read private asset content by calling assets/edit-image with an arbitrary assetId that they are not authorized to view.
The endpoint returns image bytes (or a preview redirect) without enforcing a per-asset view authorization check, leading to potential unauthorized disclosure of private files.
Details
Root cause:
- A user-controlled object reference (
assetId) is used to load and return sensitive content. - The action does not verify whether the current user is authorized to view that asset.
- This creates an authenticated IDOR / authorization bypass.
Impact
- Craft installations where private/non-public assets exist and low-privileged users can authenticate.
Resources
Affected versions
Packagist
| Package | Vulnerable | Fixed in |
|---|---|---|
| craftcms/cms | >= 4.0.0-RC1, < 4.17.8 |
4.17.8 |
| craftcms/cms | >= 5.0.0-RC1, < 5.9.14 |
5.9.14 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
craftcms/cms Packagist → 4.17.8
- composer
composer require craftcms/cms:^4.17.8
Severity breakdown
CVSS 4.0 0.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U
- Attack vector
- Network
- Attack complexity
- Low
- Attack requirements
- None
- Privileges required
- Low
- User interaction
- None
- Confidentiality (vulnerable system)
- High
- Integrity (vulnerable system)
- None
- Availability (vulnerable system)
- None
- Confidentiality (subsequent systems)
- None
- Integrity (subsequent systems)
- None
- Availability (subsequent systems)
- None
- Exploit maturity
- Unreported
CVSS 3.1 6.5
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Weakness
CWE-639: Authorization Bypass Through User-Controlled Key
The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.
How to prevent it
- Architecture and Design: For each and every data access, ensure that the user has sufficient privilege to access the record that is being requested.
- Architecture and Design, Implementation: Make sure that the key that is used in the lookup of a specific user's record is not controllable externally by the user or that any tampering can be detected.
- Architecture and Design: Use encryption in order to make it more difficult to guess other legitimate values of the key or associate a digital signature with the key so that the server can verify that there has been no tampering.
References
Advisories
Packages
Other links
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-7vrx-9684-xrf2 Craft CMS stores arbitrary content provided by unauthenticated users in session files | Medium Known exploited | Also affects craftcms/cms |
| GHSA-f3gw-9ww9-jmc3 Craft CMS Allows Remote Code Execution | Critical Known exploited | Also affects craftcms/cms |
| GHSA-x684-96hh-833x Craft CMS has a potential RCE with a compromised security key | High Known exploited | Also affects craftcms/cms |
| GHSA-2p6p-9rc9-62j9 Craft CMS has potential RCE when PHP `register_argc_argv` config setting is enabled | Critical Known exploited | Also affects craftcms/cms |
| GHSA-wg23-69c2-gjc8 Craft CMS: Passkey login accepts replayed WebAuthn assertions | Medium | Also affects craftcms/cms |
| GHSA-957r-qf9p-67xw Craft CMS: Arbitrary file read via SplFileObject in non-sandboxed template contexts | Medium | Also affects craftcms/cms |
| GHSA-596p-6jv8-775v Craft CMS: Authenticated leak of secret environment variables | Medium | Also affects craftcms/cms |
| GHSA-xxpx-f366-4xpq Craft CMS: Authorization bypass: view-only Categories user can modify category structure via structures/move-element | Medium | Also affects craftcms/cms |
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