CVE-2026-20160
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSummary
CVE-2026-20160 is a critical-severity Exposure of Resource to Wrong Sphere (CWE-668) vulnerability in Cisco Smart Software (inferred from references). Its CVSS base score is 9.8 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Cloud Instance Metadata API (T1552.005); ranked in the top 43% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and AC-4 (Information Flow Enforcement) — 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-2026-20160 is a high-severity vulnerability in Cisco Smart Software Manager On-Prem (SSM On-Prem) that exposes an internal service, enabling an unauthenticated, remote attacker to execute arbitrary commands on the underlying operating system of an affected SSM On-Prem host. The issue stems from the unintentional exposure of this service, which allows attackers to target its API. It has a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) and is associated with CWE-668 (Exposure of Resource to Wrong Sphere).
An unauthenticated, remote attacker can exploit this vulnerability by sending a crafted request to the API of the exposed internal service. Successful exploitation grants root-level privileges on the underlying operating system, potentially allowing full compromise of the SSM On-Prem host, including data exfiltration, persistence, or further lateral movement within the network.
The Cisco Security Advisory provides details on mitigation, available at https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ssm-cli-execution-cHUcWuNr.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-17956
Vulnerability Data
A vulnerability in Cisco Smart Software Manager On-Prem (SSM On-Prem) could allow an unauthenticated, remote attacker to execute arbitrary commands on the underlying operating system of an affected SSM On-Prem host. This vulnerability is due to the unintentional exposure of…
more
an internal service. An attacker could exploit this vulnerability by sending a crafted request to the API of the exposed service. A successful exploit could allow the attacker to execute commands on the underlying operating system with root-level privileges.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
—
—
- 8 hardening rules · 7 OS baselines
—
Mitigating Controls (NIST 800-53 r5) AI
Access enforcement directly stops resources from being reachable by actors outside the intended control sphere.
Information flow enforcement structurally prevents unintended cross-sphere data or resource exposure.
Least privilege reduces the set of actors that can reach a resource, limiting wrong-sphere exposure.
Security attributes enable correct sphere assignment and subsequent enforcement decisions.
Boundary protection at interfaces prevents resources from being exposed outside authorized spheres.
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.
Enforcing least-privilege authorizations directly prevents resources from being exposed outside their intended control sphere.
Network segmentation and unauthorized-access protections reduce the chance of resources being reachable by the wrong sphere.
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.
Placing systems of differing trust levels into separate domains prevents resources from being placed in a sphere where they are reachable by unintended actors.
Requiring owners to manage the full asset life cycle and remove assets from the inventory upon secure disposal helps prevent resources from being inadvertently exposed outside their intended security sphere.
Hardening callouts derived
Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).
Oracle Linux 8 (2 rules)
- V-248827 OL 8 must not have the rsh-server package installed. prevents CWE-668
- V-248823 OL 8 must not have the telnet-server package installed. prevents CWE-668
RHEL 7 (1 rule)
- V-204442 The Red Hat Enterprise Linux operating system must not have the rsh-server package installed. prevents CWE-668
Windows 10 (1 rule)
- V-220967 The Debug programs user right must only be assigned to the Administrators group. prevents CWE-668
Windows 11 (1 rule)
- V-253490 The "Debug programs" user right must only be assigned to the Administrators group. prevents CWE-668
Windows Server 2016 (1 rule)
- V-225079 The Debug programs user right must only be assigned to the Administrators group. prevents CWE-668
Windows Server 2019 (1 rule)
- V-205757 Windows Server 2019 Debug programs: user right must only be assigned to the Administrators group. prevents CWE-668
Windows Server 2022 (1 rule)
- V-254500 Windows Server 2022 debug programs user right must only be assigned to the Administrators group. prevents CWE-668