CVE-2026-54611 — InstantCMS has Remote Code Execution in package installer
InstantCMS is a free and open source content management system. Versions prior to 2.18.2 have a Remote Code Execution (RCE) issue that allows remote authenticated attackers to e…
Published: 2026-09-08 · CVSS: 5.5 · CVSS 3.1
InstantCMS is a free and open source content management system. Versions prior to 2.18.2 have a Remote Code Execution (RCE) issue that allows remote authenticated attackers to execute any PHP code via the component installer. It is possible to upload a malicious component into the server, however, it won't be installed, but upload files will be executed. Normally all php files in upload folder are not executed, however, by uploading custom .htaccess it becomes possible. Version 2.18.2 contains a fix.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7