Arbitrary file upload in Codeigniter4
CVE-2026-48062
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.
Vulnerability class: Unrestricted File Upload
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.008 (54.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 55th percentile — 54.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000
Affected products
- Codeigniter4 — versions < 4.7.3
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-48062?
- CVE-2026-48062 is a critical-severity vulnerability in Codeigniter4, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 9.8/10. Published 2026-07-17.
- How severe is CVE-2026-48062?
- Critical severity. CVSS v3 base score is 9.8 out of 10.