CVE-2026-63223: CodeIgniter: Uploaded file extension validation bypass in is_image and mime_in rules
Advisory generated from the CVE record, CISA, Exploit Observer and VEDAS: what it is, whether it is exploited, who is affected, and how to fix and detect it.
Generated by VEDAS. Scores as of 2026-11-08 00:03 UTC. Rebuilt every few hours from cve-scores, CISA KEV and vedas-signatures. How this works and its limits.
What it is
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.
Description quoted from the CVE record (assigned by GitHub_M, published 2026-07-31).
Weakness: CWE-434: Unrestricted Upload of File with Dangerous Type
How it can be exploited
Exploitable over the network with low attack complexity needing no privileges and no user interaction. Impact: confidentiality high, integrity high, availability high. CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA assessment (SSVC): CISA has no evidence of exploitation. Automatable: yes. Technical impact: total.
Public exploit evidence (Exploit Observer)
Exploit Observer found 6 code repositories naming this CVE.
Code repositories that name a CVE are often scanners, copies or fakes, and some are malware. Read the code before running anything.
See all 13 references on Exploit Observer
Live scores
- EPSS
- 0.008
low predicted chance of attack - VEDAS
- 0.987
strong exploit evidence - On CISA KEV
- Not listed
- Detection rule
- Suricata
Who is affected
| Product | Affected | Not affected |
|---|---|---|
| CodeIgniter4 | version < 4.7.4 | Not stated |
Version ranges exactly as the CVE record states them. “Before X” means X is the first fixed version.
How to fix it
No fixed version or vendor advisory is listed in the CVE record yet. Watch the vendor’s security page.
How to detect it
Suricata rules (network detection)
1 rule that alert on traffic matching this exploit: VEDAS CVE-2026-63223 CodeIgniter - Arbitrary File Upload. Add them to your Suricata rule set and reload.
Show the rules
# network-only (destructive: file-upload; no safe active check)
alert http $EXTERNAL_NET any -> $HTTP_SERVERS $HTTP_PORTS (msg:"VEDAS CVE-2026-63223 CodeIgniter - Arbitrary File Upload"; flow:established,to_server; http.method; content:"POST"; http.uri; content:"avatar"; nocase; fast_pattern; http.request_body; content:"filename="; nocase; content:".php"; nocase; classtype:web-application-attack; reference:cve,CVE-2026-63223; reference:url,https://www.exploit.observer/?keyword=CVE-2026-63223&match=exact; reference:url,https://subdomain.center/?engine=ammonites&keyword=codeigniter&match=exact; metadata:signature_type network_only; sid:1019073; rev:1;)
CVE-2026-63223.rules on GitHub
References
Other references
- https://github.com/codeigniter4/CodeIgniter4/security/advisories/GHSA-mmj4-63m4-r6h5 (x_refsource_CONFIRM)
- https://github.com/codeigniter4/CodeIgniter4/commit/b6e9a4fa1dca2df3d3f261bdf61532df8c6420aa (x_refsource_MISC)
- https://github.com/codeigniter4/CodeIgniter4/releases/tag/v4.7.4 (x_refsource_MISC)
Other databases
Where this comes from
This advisory is generated automatically by VEDAS from: CVE.org record, cve-scores (EPSS and VEDAS), Exploit Observer, vedas-signatures. Text in quotes is reproduced from the source; everything else is a fixed template filled with source fields. Nothing here is written by a language model. Check the vendor advisory before acting, and read how VEDAS and Exploit Observer work, and their limits.
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