CVE-2026-56384
Craft CMS: Authenticated "assets/preview-thumb" discloses signed fallback transform preview link to CP users without asset-view permission
描述
### Summary A user with Control Panel access but without permission to view a target private asset can call `assets/preview-thumb` and receive preview HTML that contains a signed fallback transform link for that private asset. ### Details Root-cause analysis: 1. The endpoint accepts an attacker-controlled `assetId`. 2. Asset is resolved, and thumbnail HTML is returned. 3. No explicit asset-view permission check is performed before preview generation. ### Impact Type: 1. Missing authorization 2. Unauthorized preview-link disclosure Affected deployments: 1. Craft sites with control panel users who have partial permissions and private assets. Security consequence: 1. A control panel user without asset-view permission can still obtain signed preview transform link data for private assets. 2. This may increase private asset exposure risk depending on deployment and endpoint chaining. ## Resources https://github.com/craftcms/cms/commit/d30df3112220db1ffd6726a3ed11857014c7fb27
如何修補 CVE-2026-56384
要修補 CVE-2026-56384,請將受影響套件升級到下列已修補版本。
- —升級至 4.17.8 或更新版本
CVE-2026-56384 正在被利用嗎?
低 — EPSS 為 0.2%,目前沒有觀察到大規模利用活動。
受影響套件(1)
- >= 4.0.0-RC1, < 4.17.8
CVSS 分數
| 來源 | 版本 | 嚴重程度 | 向量 |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N |