جزئیات آسیب‌پذیری

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.

• https://github.com/codeigniter4/CodeIgniter4/security/advisories/GHSA-2gr4-ppc7-7mhx x_refsource_CONFIRM
• https://github.com/codeigniter4/CodeIgniter4/commit/29299349e7d232e9532767c7cefaed30957309be x_refsource_MISC
• https://github.com/codeigniter4/CodeIgniter4/releases/tag/v4.7.3 x_refsource_MISC