CVE-2026-33158: Craft CMS: Low-privilege users could read private asset contents when editing an asset (IDOR)

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-03-24 · updated 2026-06-17
Weakness: CWE-639

Description

Craft CMS is a content management system (CMS). From version 4.0.0-RC1 to before version 4.17.8 and from version 5.0.0-RC1 to before version 5.9.14, 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. This issue has been patched in versions 4.17.8 and 5.9.14.

Affected products

craftcms cms: from 4.0.0 (excl.) before 4.17.8; from 5.0.0 (excl.) before 5.9.14; 4.0.0, 4.0.0-rc1, 4.0.0-rc2, 4.0.0-rc3, 5.0.0, 5.0.0-rc1 — fixed in 4.17.8, 5.9.14

How to fix

Upgrade to a fixed version: craftcms cms 4.17.8, 5.9.14. Check the vendor advisory for mitigations.

References

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