CVE-2026-56702: Adminer before 5.4.3 Unrestricted File Upload via AdminerFileUpload

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-25 · updated 2026-10-12
Weakness: CWE-434

Description

Adminer versions before 5.4.3 contain an unrestricted file upload vulnerability in the AdminerFileUpload plugin that allows authenticated users to upload PHP files by exploiting a permissive default extension allowlist. Attackers can upload PHP webshells to columns ending in _path and execute arbitrary code as the web-server user when uploadPath is web-served.

Affected products

vrana adminer: before 5.4.3 — fixed in 5.4.3

How to fix

Upgrade to a fixed version: vrana adminer 5.4.3. Check the vendor advisory for mitigations.

References

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

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