What’s Vulnerable › Vulnerabilities

CVE-2026-21861: baserCMS: OS Command Injection Leading to Remote Code Execution (RCE)

• Severity: high (CVSS 7.2 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.3% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-03-31 · updated 2026-06-17
• Weakness: CWE-78

Description

baserCMS is a website development framework. Prior to version 5.2.3, baserCMS contains an OS command injection vulnerability in the core update functionality. An authenticated administrator can execute arbitrary OS commands on the server due to improper handling of user-controlled input that is directly passed to exec() without sufficient validation or escaping. This issue has been patched in version 5.2.3.

Affected products

• baserproject basercms: before 5.2.3 — fixed in 5.2.3

How to fix

Upgrade to a fixed version: baserproject basercms 5.2.3. Check the vendor advisory for mitigations.

References

• https://basercms.net/security/JVN_20837860
• https://github.com/baserproject/basercms/releases/tag/5.2.3
• https://github.com/baserproject/basercms/security/advisories/GHSA-qxmc-6f24-g86g
• https://github.com/baserproject/basercms/security/advisories/GHSA-qxmc-6f24-g86g

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