CVE-2026-103476

yii2-starter-kit through 4.2.0 fails to validate article publication status in the attachment-download endpoint, allowing unauthenticated attackers to download files from draft articles. Attackers can enumerate sequential attachment identifiers to retrieve files from unpublished articles without authentication or authorization checks.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/yii-starter-kit/yii2-starter-kit
https://github.com/yii-starter-kit/yii2-starter-kit/blob/cc2c451e8c959c7300b04efea597706a38609f58/frontend/controllers/ArticleController.php#L69
https://github.com/yii-starter-kit/yii2-starter-kit/issues/797
https://www.vulncheck.com/advisories/yii2-starter-kit-through-4.2.0-unauthorized-file-download-via-attachment-download

Configurations

No configuration.

History

30 Sep 2026, 18:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-30 18:18

Updated : 2026-10-01 16:17

NVD link : CVE-2026-103476

Mitre link : CVE-2026-103476

CVE.ORG link : CVE-2026-103476

JSON object : View

Products Affected

No product.

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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