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Critical

CodeIgniter: Uploaded file extension validation bypass in `is_image` and `mime_in` rules

  • Disclosed: 07.08.2026
  • Updated: 11.10.2026 10:22

Impact

This is an unsafe file upload validation vulnerability that can lead to remote code execution in vulnerable application configurations.

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
  • place uploads in a web-accessible directory where PHP files can execute

Patches

Upgrade to v4.7.4 or later.

Workarounds

  • Save uploads outside the public web root, preferably under writable/uploads.
  • Use $file->store() or $file->move($path, $file->getRandomName()) instead of preserving the original client filename.
  • Disable script execution in any public upload directory.
  • Manually verify the client filename extension before moving the file.
  • For image uploads, reject files when $file->getClientExtension() is not an allowed image extension.
  • For exact MIME-type validation, reject files when $file->getClientExtension() does not match $file->guessExtension().

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
Composer package codeigniter4/framework < 4.7.4 4.7.4

References

CVSS score 9.8/10
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE)
CWE-434
Platform
Composer
Package
codeigniter4/framework
Disclosed
07.08.2026
Updated
11.10.2026 10:22

Sources and licenses

OSV / GitHub Advisory Database - GHSA-mmj4-63m4-r6h5 - CC BY 4.0

Vulnerability history: codeigniter4/framework

All published vulnerabilities of this package (Composer package), newest first. Shows whether this is a one-off slip or a package that needs watching.

All (19) in the archive
Total entries
19
First → latest
01.2022 08.2026
Without a fix
1
Exploited in attacks
0

Severity breakdown

  • Critical 6
  • High 8
  • Medium 4
  • Low 1

Disclosures per year

Severity:
  1. CodeIgniter: Uploaded file extension validation bypass in `is_image` and `mime_in` rules this entry
    Critical · 9.8 CVE-2026-63223 < 4.7.4 4.7.4
  2. CodeIgniter: Path traversal in UploadedFile::move() when using client-provided filenames
    High · 7.5 CVE-2026-63222 < 4.7.4 4.7.4
  3. CodeIgniter: SQL injection in Query Builder deleteBatch() when used with where() conditions
    Critical · 9.4 CVE-2026-63221 >= 4.3.0, < 4.7.4 4.7.4
  4. CodeIgniter4 has a validation bypass when uploading file extensions via `ext_in` rule
    Critical · 9.8 CVE-2026-48062 < 4.7.3 4.7.3
  5. CodeIgniter4's ImageMagick Handler has Command Injection Vulnerability
    Critical · 9.8 CVE-2025-54418 < 4.6.2 4.6.2
  6. CodeIgniter4 DoS Vulnerability
    High · 7.5 CVE-2024-29904 < 4.4.7 4.4.7
  7. CodeIgniter4 vulnerable to information disclosure when detailed error report is displayed in production environment
    High · 7.5 CVE-2023-46240 < 4.4.3 4.4.3
  8. Remote Code Execution Vulnerability in Validation Placeholders in CodeIgniter4
    Critical · 9.8 CVE-2023-32692 < 4.3.5 4.3.5
  9. CodeIgniter4 Potential Session Handlers Vulnerability
    High · 8.6 CVE-2022-46170 < 4.2.11 4.2.11
  10. CodeIgniter4 allows spoofing of IP address when using proxy
    High · 7.0 CVE-2022-23556 < 4.2.11 4.2.11
  11. CodeIgniter Improper Privilege Management
    High · 8.8 CVE-2020-10793 <= 4.0.0 no fix
  12. CodeIgniter HTTP Header Injection
    High · 7.5 CVE-2017-1000247 >= 3.1.3, < 3.1.4 3.1.4
  13. Remote CLI Command Execution Vulnerability in CodeIgniter4
    Critical · 9.4 CVE-2022-24711 < 4.1.9 4.1.9
  14. Deserialization of Untrusted Data in Codeigniter4
    High · 7.7 CVE-2022-21647 < 4.1.6 4.1.6

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