CVE-2026-103474 yii2-starter-kit through 4.2.0 Unrestricted File Upload RCE
Authenticated managers can upload PHP files to execute arbitrary code on the server due to missing file type validation.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-103474?
CVE-2026-103474 is a high-severity vulnerability in yii2-starter-kit, published on 30 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
yii2-starter-kit through 4.2.0 fails to validate file types in the backend storage upload actions, allowing authenticated managers to upload PHP files. Attackers with manager role can upload PHP scripts to the web-accessible storage directory and request them to execute arbitrary code on the server.
Weakness: CWE-434
Which versions are affected by CVE-2026-103474?
How do I fix CVE-2026-103474?
No fix has been published for CVE-2026-103474 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-103474 being exploited?
There is no known exploitation of CVE-2026-103474 in the wild and no public exploit code.
Sources
Also known as GHSA-hfh8-jhpw-h99w.