CodeIgniter: Uploaded file extension validation bypass in `ext_in` rule
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-434.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| codeigniter4 | CodeIgniter4 | before 4.7.3 | 4.7.3 | Patch available | CNA |
| — | codeigniter4/framework (Packagist) | before 4.7.3 | 4.7.3 | Patch available | GHSA-2gr4-ppc7-7mhx |
- CodeIgniter4 Vendorcodeigniter4 Affected before 4.7.3 Fixed in 4.7.3 Patch available CNA
- codeigniter4/framework (Packagist) Vendor— Affected before 4.7.3 Fixed in 4.7.3 Patch available GHSA-2gr4-ppc7-7mhx
CPE names Threatist (inferred) · 1
Inferred from how NVD named this product before; not given by a source.
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:codeigniter:codeigniter:*:*:*:*:*:*:*:* | — | — | codeigniter4 |
- cpe:2.3:a:codeigniter:codeigniter:*:*:*:*:*:*:*:* Versions — — ·codeigniter4
Remediation
- Fix · CNA CodeIgniter4 (codeigniter4) Fixed in 4.7.3
- Fix · GHSA-2gr4-ppc7-7mhx codeigniter4/framework (Packagist) Fixed in 4.7.3 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-48062
- 2026-10-03 Alias added: GHSA-2gr4-ppc7-7mhx
References
Other 7
- https://github.com/codeigniter4/CodeIgniter4/security/advisories/GHSA-2gr4-ppc7-7mhx
- https://github.com/codeigniter4/CodeIgniter4/commit/29299349e7d232e9532767c7cefaed30957309be
- https://github.com/codeigniter4/CodeIgniter4/releases/tag/v4.7.3
- https://codeigniter.com/user_guide/libraries/uploaded_files.html#moving-files
- https://codeigniter.com/user_guide/libraries/validation.html#rules-for-file-uploads
- https://github.com/codeigniter4/CodeIgniter4
- https://github.com/codeigniter4/CodeIgniter4/blob/develop/CHANGELOG.md
More codeigniter4 vulnerabilities
- TI-2014-07135 CodeIgniter before 3.0 and Kohana 3.2.3 and earlier and 3.3.x through 3.3.2 make it… CVSS 3.0CRITICAL 9.8
- TI-2022-16370 SameSite may allow cross-site request forgery (CSRF) protection to be bypassed CVSS 3.1HIGH 8.8
- TI-2022-06025 Deserialization of Untrusted Data in Codeigniter4 CVSS 3.1CRITICAL 9.8
- TI-2024-27591 A Cross-Site Request Forgery (CSRF) in Codeigniter 3.1.13 allows attackers to arbitrarily… CVSS 3.1HIGH 7.5
- TI-2014-07136 CodeIgniter before 2.2.0 makes it easier for attackers to decode session cookies by… CVSS 3.0CRITICAL 9.8
- TI-2024-19671 CodeIgniter4 Language class DoS Vulnerability CVSS 3.1HIGH 7.5
Sources
- CVE-2026-48062 · CVE Program
- CVE-2026-48062 · NVD
- FIRST EPSS
- GHSA-2gr4-ppc7-7mhx · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences