CVE-2026-61457

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.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/getgrav/grav/security/advisories/GHSA-66v2-vxxf-xc3v
https://www.vulncheck.com/advisories/grav-before-remote-code-execution-via-file-upload-extension-bypass
https://github.com/getgrav/grav/security/advisories/GHSA-66v2-vxxf-xc3v

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-15 12:18

Updated : 2026-07-15 19:50

NVD link : CVE-2026-61457

Mitre link : CVE-2026-61457

CVE.ORG link : CVE-2026-61457

JSON object : View

Products Affected

No product.

CWE

CWE-434

Unrestricted Upload of File with Dangerous Type

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