Unrestricted File Upload Vulnerability in Adminer by Adminer
CVE-2026-56702

7.1HIGH

Key Information:

Vendor

Vrana

Status
Adminer
Vendor
CVE Published:
25 August 2026

What is CVE-2026-56702?

In Adminer versions prior to 5.4.3, the AdminerFileUpload plugin is susceptible to an unrestricted file upload flaw. This issue enables authenticated users to upload malicious PHP files by exploiting a permissive default extension allowlist. When the upload path is web-accessible, this vulnerability permits attackers to upload PHP webshells and execute arbitrary code with the same privileges as the web server user, potentially compromising the entire environment.

Affected Version(s)

adminer 0 < 5.4.3

adminer 5.4.3

References

https://github.com/vrana/adminer/security/advisories/GHSA...
vendor-advisory
https://www.vulncheck.com/advisories/adminer-before-unres...
third-party-advisory

CVSS V4

Score:
7.1
Severity:
HIGH
Confidentiality:
High
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

riodrwn
.