CVE-2026-48062
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk36th percentile - higher than 36% of all known CVEs
Summary
CodeIgniter before version 4.7.3 contains a vulnerability in the ext_in validation rule, which checks the extension based on the detected MIME type rather than the actual file extension. A file named shell.php with GIF content can pass validation, potentially leading to arbitrary code execution.
Risk Assessment
An attacker can upload a PHP file disguised as an image, which when saved on the server can be executed, leading to remote code execution and server compromise.
Recommendation
Update CodeIgniter to version 4.7.3 or later.
Original NVD description (English source)
CodeIgniter is a PHP full-stack web framework. Prior to 4.7.3, the ext_in upload validation rule in system/Validation/StrictRules/FileRules.php checked the MIME-derived guessed extension instead of the client-provided filename extension. As a result, an uploaded file named shell.php containing GIF-like content could pass validation such as uploaded[avatar]|is_image[avatar]|mime_in[avatar,image/gif]|ext_in[avatar,gif] because the detected MIME type maps to gif, even though the uploaded filename extension is php. Applications are impacted if they accept user-controlled uploads, rely on ext_in to validate the uploaded filename extension, save uploaded files using the original client filename with $file->move($path), store uploads in a web-accessible directory, and allow PHP or other executable files to run from that directory. In those conditions, this may lead to arbitrary code execution. This issue is fixed in version 4.7.3.