9.8
CRITICAL CVSS 3.1
CVE-2026-63223
CodeIgniter: Uploaded file extension validation bypass in is_image and mime_in rules
Description

CodeIgniter is a PHP full-stack web framework. Prior to 4.7.4, the is_image and mime_in upload validation rules do not independently enforce a safe client filename extension, allowing a remote attacker to upload executable content when an application preserves the client filename and stores uploads in a web-accessible script-enabled directory. Applications are impacted when they validate uploads using is_image or mime_in without an independent safe extension check (such as ext_in on patched versions), save uploaded files using the client-supplied filename, and place uploads in a web-accessible directory where PHP files can execute. This issue is fixed in version 4.7.4.

INFO

Published Date :

July 31, 2026, 6:16 a.m.

Last Modified :

July 31, 2026, 6:16 a.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-63223 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 CRITICAL [email protected]
CVSS 3.1 CRITICAL MITRE-CVE
Solution
Update CodeIgniter to version 4.7.4 to fix upload validation rules and prevent executable file uploads.
  • Update CodeIgniter to version 4.7.4.
  • Implement independent safe extension checks for uploads.
  • Avoid preserving client filenames for uploads.
  • Store uploads outside web-accessible script-enabled directories.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-63223.

URL Resource
https://github.com/codeigniter4/CodeIgniter4/commit/b6e9a4fa1dca2df3d3f261bdf61532df8c6420aa
https://github.com/codeigniter4/CodeIgniter4/releases/tag/v4.7.4
https://github.com/codeigniter4/CodeIgniter4/security/advisories/GHSA-mmj4-63m4-r6h5
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-63223 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-63223 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-63223 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-63223 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Jul. 31, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'codeigniter4', 'product': 'CodeIgniter4', 'versions': [{'status': 'affected', 'version': '< 4.7.4'}]}]
    Added Description CodeIgniter is a PHP full-stack web framework. Prior to 4.7.4, the is_image and mime_in upload validation rules do not independently enforce a safe client filename extension, allowing a remote attacker to upload executable content when an application preserves the client filename and stores uploads in a web-accessible script-enabled directory. Applications are impacted when they validate uploads using is_image or mime_in without an independent safe extension check (such as ext_in on patched versions), save uploaded files using the client-supplied filename, and place uploads in a web-accessible directory where PHP files can execute. This issue is fixed in version 4.7.4.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-434
    Added Reference https://github.com/codeigniter4/CodeIgniter4/commit/b6e9a4fa1dca2df3d3f261bdf61532df8c6420aa
    Added Reference https://github.com/codeigniter4/CodeIgniter4/releases/tag/v4.7.4
    Added Reference https://github.com/codeigniter4/CodeIgniter4/security/advisories/GHSA-mmj4-63m4-r6h5
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.