What is CVE-2026-54611?

CVE-2026-54611 is a medium-severity vulnerability in Instantsoft Icms2, classified under Code Injection. CVSS score: 5.5/10. Published 2026-09-08.

How severe is CVE-2026-54611?

Medium severity. CVSS v3 base score is 5.5 out of 10.

RCE in Instantsoft Icms2

CVE-2026-54611

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.

Vulnerability class: RCE (Remote Code Execution)

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H.

Affected products

Instantsoft Icms2 — versions < 2.18.2

Weakness classification (CWE)

References

security-advisories@github.com (x_refsource_CONFIRM)
security-advisories@github.com (x_refsource_MISC)

Frequently asked questions

What is CVE-2026-54611?: CVE-2026-54611 is a medium-severity vulnerability in Instantsoft Icms2, classified under Code Injection. CVSS score: 5.5/10. Published 2026-09-08.
How severe is CVE-2026-54611?: Medium severity. CVSS v3 base score is 5.5 out of 10.