High severity · published Mar 31, 2026
CVE-2026-21861
baserCMS: OS Command Injection Leading to Remote Code Execution (RCE)
7.2
CVSS
2.3%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.3% · higher than 83% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
BA
basercms · baserproject
< 5.2.3 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-21861
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-21861
Vendor Advisory
https://basercms.net/security/JVN_20837860
Release Notes
https://github.com/baserproject/basercms/releases/tag/5.2.3
Exploit
https://github.com/baserproject/basercms/security/advisories/GHSA-qxmc-6f24-g86g
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