Raw vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XSummary
CVE-2026-6644 is a critical-severity OS Command Injection (CWE-78) vulnerability in Asustor Data Master. Its CVSS base score is 9.4 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked in the top 29% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2026-6644 is a command injection vulnerability (CWE-78) in the PPTP VPN Clients on the ADM, stemming from insufficient validation of user-supplied input before it is passed to a system shell. This flaw enables an administrative user to break out of the restricted web environment and execute arbitrary code on the underlying operating system. Affected products include ADM versions from 4.1.0 through 4.3.3.RR42, as well as from 5.0.0 through 5.1.2.REO1. The vulnerability carries a CVSS v3.1 base score of 9.1 (AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H) and was published on 2026-04-20.
The attack requires privileged access as an administrative user (PR:H) and can be carried out remotely over the network (AV:N) with low complexity (AC:L) and no user interaction (UI:N). Successful exploitation grants remote code execution (RCE), allowing full compromise of the system through arbitrary code execution on the host operating system, with changed scope (S:C) and high impact across confidentiality, integrity, and availability.
Advisories providing further details, including potential patches and mitigation guidance, are available from ASUSTOR at https://https://www.asustor.com/security/security_advisory_detail?id=55 and an independent analysis at https://uky007.github.io/CVE-2026-6644/.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-23784
Vulnerability Data
A command injection vulnerability was found in the PPTP VPN Clients on the ADM. The vulnerability allows an administrative user to break out of the restricted web environment and execute arbitrary code on the underlying operating system. This occurs due…
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to insufficient validation of user-supplied input before it is passed to a system shell. Successful exploitation allows an attacker to achieve Remote Code Execution (RCE) and fully compromise the system. Affected products and versions include: from ADM 4.1.0 through ADM 4.3.3.RR42 as well as from ADM 5.0.0 through ADM 5.1.2.REO1.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V1.2.5V1.2.8V15.2.5
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation can discover missing or incorrect command sanitization during development.
Input validation directly neutralizes or rejects special characters that would otherwise alter OS command structure.
Least privilege reduces the permissions available to any process that could be subverted by injected commands.
Least functionality restricts available OS commands and interpreters, limiting the blast radius of injection.
Secure engineering principles require proper neutralization of untrusted input before command construction.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
PR.PS-06's SDLC practices directly require secure coding and input handling that blocks command-injection defects, yet the single broad outcome leaves many specific neutralization vectors and verification gaps unaddressed.
Routine patching/maintenance can remediate known command-injection CVEs in dependencies (partial forward) but does nothing to stop developers from introducing improper neutralization in custom code (none reverse).
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing and code review target insecure use of operating-system command interfaces, catching command-injection flaws introduced during development.