baserCMS: OS Command Injection Leading to Remote Code Execution (RCE)
Priority HIGH 74CWE-78Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- High
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-78.
Summary
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.
Why it matters now
Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.02322 83rd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed basercms (baserproject): 5.2.3baserproject/basercms (Packagist): 5.2.3
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| baserproject | basercms | before 5.2.3 | 5.2.3 | Patch available | CNA |
| — | baserproject/basercms (Packagist) | before 5.2.3 | 5.2.3 | Patch available | GHSA-qxmc-6f24-g86g |
- basercms Vendorbaserproject Affected before 5.2.3 Fixed in 5.2.3 Patch available CNA
- baserproject/basercms (Packagist) Vendor— Affected before 5.2.3 Fixed in 5.2.3 Patch available GHSA-qxmc-6f24-g86g
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:basercms:basercms:*:*:*:*:*:*:*:* | before 5.2.3 | Vulnerable | baserproject |
- cpe:2.3:a:basercms:basercms:*:*:*:*:*:*:*:* Versions before 5.2.3 Vulnerable ·baserproject
Remediation
- Fix · CNA basercms (baserproject) Fixed in 5.2.3
- Fix · GHSA-qxmc-6f24-g86g baserproject/basercms (Packagist) Fixed in 5.2.3 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-21861
- 2026-10-03 Alias added: GHSA-qxmc-6f24-g86g
References
More baserproject Basercms vulnerabilities
- TI-2025-23967 baserCMS: unsafe File Upload Leading to Remote Code Execution (RCE) CVSS 3.1HIGH 8.7
- TI-2026-23707 baserCMS: Mail Form Acceptance Bypass via Public API CVSS 3.1MEDIUM 5.3
- TI-2023-10935 baserCMS File Uploader Remote Code Execution (RCE) vulnerability CVSS 3.1CRITICAL 9.8
- TI-2023-10936 baserCMS allows any file to be uploaded CVSS 3.1CRITICAL 9.8
- TI-2023-23483 baserCMS Code Injection Vulnerability in Mail Form Feature CVSS 3.1CRITICAL 9.8
- TI-2026-23709 baserCMS: OS command injection vulnerability in installer CVSS 4.0CRITICAL 9.2
Sources
- CVE-2026-21861 · CVE Program
- CVE-2026-21861 · NVD
- FIRST EPSS
- GHSA-qxmc-6f24-g86g · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences