CVE-2026-103475

yii2-starter-kit through 4.2.0 exposes the Yii debug and Gii modules to all IP addresses by setting allowedIPs to ['*'] in its default development configuration. Unauthenticated remote attackers can access the debug endpoint to read sensitive data including session cookies and database queries, or access the Gii endpoint to generate and write PHP files into the application directory.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

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/common/config/web.php#L21
https://github.com/yii-starter-kit/yii2-starter-kit/issues/797
https://www.vulncheck.com/advisories/yii2-starter-kit-through-4.2.0-debug-and-gii-module-exposure

Configurations

No configuration.

History

30 Sep 2026, 18:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-30 18:18

Updated : 2026-09-30 20:17

NVD link : CVE-2026-103475

Mitre link : CVE-2026-103475

CVE.ORG link : CVE-2026-103475

JSON object : View

Products Affected

No product.

CWE

CWE-489

Active Debug Code

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