Arbitrary file upload in CodeIgniter4 - #VU137010
Published: July 7, 2026
Vulnerability identifier: #VU137010
CSH Severity: High
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber
CVE-ID: N/A
CWE-ID: CWE-434
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: CodeIgniter
Affected software:
CodeIgniter4
CodeIgniter4
Detailed vulnerability description
The vulnerability allows a remote attacker to execute arbitrary code.
The vulnerability exists due to unrestricted upload of file with dangerous type in the `is_image` and `mime_in` file upload validation rules when validating uploaded files. A remote attacker can upload a crafted file with a dangerous extension to execute arbitrary code.
Applications are impacted when uploaded files are saved using the client-supplied filename and placed in a web-accessible directory where PHP files can execute.
Remediation
Install security update from vendor's website.