CVE-2026-2026
Tenable Nessus Agent ≤ 11.0.4
Raw vector
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/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-2026-2026 is a medium-severity Incorrect Default Permissions (CWE-276) vulnerability in Tenable Nessus Agent. Its CVSS base score is 5.4 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Services File Permissions Weakness (T1574.010); ranked at the 1th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and AC-6 (Least Privilege) — see the control section below for these in your framework.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-7381
Vulnerability Data
A vulnerability has been identified where weak file permissions in the Nessus Agent directory on Windows hosts could allow unauthorized access, potentially permitting Denial of Service (DoS) attacks.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Weak directory permissions on Windows service-related agent files directly match the described Services File Permissions Weakness.
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
Mitigating Controls (NIST 800-53 r5) AI
Directly enforces file and directory access permissions to block unauthorized users from accessing or tampering with the Nessus Agent directory.
Requires assignment of only the minimum necessary permissions on the agent directory, directly mitigating the CWE-276 weak-permission flaw.
Mandates secure baseline configuration settings, including explicit file-system permissions that would prevent the reported unauthorized-access condition.
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.
Hardened baselines and configuration management explicitly require correct default file permissions.
Defining and enforcing least-privilege access permissions directly prevents overly permissive defaults at install time.
Lifecycle management can encompass permission settings, yet the control is too broad to specifically mitigate incorrect defaults.
Secure SDLC practices include establishing secure defaults, but address only the development-phase portion of the weakness.
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.
Standard templates that restrict access to utility programs and host parameter settings prevent the assignment of overly permissive default permissions on critical resources.
Hardening callouts derived
Configuration rules from DISA STIG baselines that reduce the attack surface for weaknesses of the type cited by this CVE. Derived transitively via CVE→CWE→STIG over `controls_xwalks` (authoritative rows only).
Windows Server 2016 (1 rule)
- V-224833 Permissions for program file directories must conform to minimum requirements. via CWE-276
Windows Server 2019 (2 rules)
- V-205735 Windows Server 2019 permissions for program file directories must conform to minimum requirements. via CWE-276
- V-205736 Windows Server 2019 permissions for the Windows installation directory must conform to minimum requirements. via CWE-276
Windows Server 2022 (2 rules)
- V-254252 Windows Server 2022 permissions for program file directories must conform to minimum requirements. via CWE-276
- V-254253 Windows Server 2022 permissions for the Windows installation directory must conform to minimum requirements. via CWE-276