CVE-2026-27760 CRITICAL

CVE-2026-27760: OpenCATS PHP Code Injection via installer AJAX endpoint

Vendor Opencats
Product OpenCATS
Weakness CWE-94 · Code injection
Published April 28, 2026
Last update May 11, 2026

CVSS base score

9.2/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

What the vulnerability does

Description

OpenCATS prior to commit 3002a29 contains a PHP code injection vulnerability in the installer AJAX endpoint that allows unauthenticated attackers to execute arbitrary code by injecting PHP statements into the databaseConnectivity action parameter. Attackers can break out of the define() string context in config.php using a single quote and statement separator to inject malicious PHP code that persists and executes on every subsequent page load when the installation wizard remains incomplete.

Key dates

Disclosure timeline

April 28, 2026 CVE published
May 11, 2026 Record updated