CVE-2026-61457 Grav before 1.0.3 Remote Code Execution via File Upload Extension Bypass
Attackers with media write permissions can upload malicious files using double extensions to achieve remote code execution on Grav CMS installations.
- 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-2026-61457?
CVE-2026-61457 is a medium-severity vulnerability in getgrav grav, published on 15 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
The Grav API plugin (getgrav/grav-plugin-api) before 1.0.3 contains a file upload extension bypass in the API media controller. HandlesMediaUploads::validateFileExtension() inspects only the final file extension via pathinfo($filename, PATHINFO_EXTENSION), so a user with api.media.write permission can upload a file with a double extension such as shell.php.jpg to bypass the dangerous extensions blocklist. The web server may then execute the file as PHP, resulting in remote code execution.
Weakness: CWE-434
Which versions are affected by CVE-2026-61457?
How do I fix CVE-2026-61457?
No fix has been published for CVE-2026-61457 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-61457 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-61457 exists.
Sources
Also known as CVE-2026-61606, GHSA-66v2-vxxf-xc3v, GHSA-7wcr-m737-mchr.