A AegiFlow
MEDIUMCVSS 5.3

GHSA-xj2c-g5xp-4p47

Duplicate Advisory: Craft CMS: Authenticated "assets/preview-thumb" discloses signed fallback transform preview link to CP users without asset-view permission

Published
2026-06-21
Modified
2026-08-06
Sources
github-advisory

Summary

## Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-x76w-8c62-48mg. This link is maintained to preserve external references. ## Original Description Craft CMS contains a missing authorization vulnerability in the assets/preview-thumb endpoint. A Control Panel user without permission to view a target private asset can call the endpoint with an attacker-controlled assetId and receive preview HTML containing a signed fallback transform preview link for that private asset, because no asset-view permission check is performed before preview generation. This affects versions >= 4.0.0-RC1, = 5.0.0-RC1, <= 5.9.13, and is fixed in 4.17.8 and 5.9.14.

Affected packages

EcosystemPackageAffected versionsFixed versions
Packagistcraftcms/cms

Remediation: No patched version is listed by GitHub.

References

Includes data from the GitHub Advisory Database, licensed under CC-BY 4.0.