CVE-2026-30877 baserCMS: OS Command Injection in the baserCMS Update Functionality

Critical 9.1 Published 31 Mar 2026 Updated 2 Apr 2026

An authenticated administrator can execute arbitrary OS commands on the server via the update functionality in baserCMS.

Exploited in the wild: Not known
Login needed: An administrator
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2026-30877?

CVE-2026-30877 is a critical command injection vulnerability in Basercms Basercms, published on 31 Mar 2026. An attacker needs administrator access to exploit it, with no action from the victim.

Official description

baserCMS is a website development framework. Prior to version 5.2.3, there is an OS command injection vulnerability in the update functionality. Due to this issue, an authenticated user with administrator privileges in baserCMS can execute arbitrary OS commands on the server with the privileges of the user account running baserCMS. This issue has been patched in version 5.2.3.

Weakness: CWE-78

Which versions are affected by CVE-2026-30877?

2 open source packages ship an affected version, including baserproject/basercms. It affects 1 product.

Package	Affected	Fixed in
`baserproject/basercms` Packagist	All versions	`5.2.3`
`baserproject/basercms` Packagist	All versions	`5.2.3`

Products include Basercms Basercms.

How do I fix CVE-2026-30877?

Upgrade baserproject/basercms to 5.2.3 or later.

Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.

Is CVE-2026-30877 being exploited?

There is no known exploitation of CVE-2026-30877 in the wild and no public exploit code.

All Basercms Basercms vulnerabilities

Sources

Also known as GHSA-m9g7-rgfc-jcm7.