# CVE-2026-56702: Adminer AdminerFileUpload PHP file upload leading to RCE

Source: https://junglewise.ai/threats/cve-2026-56702-adminer-adminerfileupload-php-file-upload-leading-to-rce  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-25. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-56702 · Severity: high · CVSS 8.8 · Published 2026-08-25

Adminer is a web-based database management tool used for administrative access to databases. The AdminerFileUpload plugin shipped with Adminer before version 5.4.3 contains a default configuration that permits uploading PHP executable files to the web server, allowing authenticated users to upload and execute arbitrary code with the privileges of the web server process.

## Quick answers

**Is CVE-2026-56702 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-56702 being exploited in the wild.

**How severe is CVE-2026-56702?** High severity, with a CVSS score of 8.8, published 25 August 2026.

**Which products and versions are affected?** vrana Adminer before 5.4.3.

**Is there a fix for CVE-2026-56702?** A patch was published on 2026-07-09: Patched in Adminer 5.4.3 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-56702 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-56702?** Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is an insecure-default and unrestricted-upload issue (CWE-1188, CWE-434) in the AdminerFileUpload plugin. The plugin accepts file uploads for columns ending in _path and uses a default extension allowlist of [a-zA-Z0-9]+, which matches executable extensions including php, phtml, phar, and mixed-case variants. The validation regex ~(\.($this->extensions))?$~ anchors an optional group at end-of-string, meaning it never rejects any filename—it only strips the extension when a restrictive allowlist is configured. An authenticated user, including low-privilege Adminer Editor end-users, can upload a PHP webshell. When uploadPath is web-served as a PHP-executable directory (the plugin's documented configuration), the attacker gains remote code execution as the web-server user. The vulnerability requires authentication but no special privileges or user interaction. A patch is available in Adminer 5.4.3 and later, and the issue is resolved by configuring a restrictive extensions allowlist.

## Affected products

- vrana Adminer before 5.4.3

## Timeline

- 2026-07-09: advisory: GitHub Security Advisory (GHSA-vcvj-rwwm-x6g5) published
- 2026-08-25: disclosed: CVE-2026-56702 published on NVD
- 2026-07-09: patched: Patched in Adminer 5.4.3

## References

- [https://github.com/vrana/adminer/security/advisories/GHSA-vcvj-rwwm-x6g5](https://github.com/vrana/adminer/security/advisories/GHSA-vcvj-rwwm-x6g5)
- [https://www.vulncheck.com/advisories/adminer-before-unrestricted-file-upload-via-adminerfileupload](https://www.vulncheck.com/advisories/adminer-before-unrestricted-file-upload-via-adminerfileupload)