CVE-2026-103476

Description

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 Attackers can enumerate sequential attachment identifiers to retrieve files from unpublished articles without authentication or authorization checks.

References

• 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