CVE-2026-20126
Cisco Catalyst Sd-Wan Manager ≤ 20.9.8.2
Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HSummary
CVE-2026-20126 is a high-severity Incorrect Use of Privileged APIs (CWE-648) vulnerability in Cisco Catalyst Sd-Wan Manager. Its CVSS base score is 8.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Abuse Elevation Control Mechanism (T1548); ranked at the 22th 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 SA-11 (Developer Testing and Evaluation) and AC-3 (Access 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-2026-20126 is a privilege escalation vulnerability in Cisco Catalyst SD-WAN Manager, stemming from an insufficient user authentication mechanism in the REST API. This flaw affects the software's underlying operating system, enabling an authenticated attacker with low privileges to elevate access. The vulnerability has a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) and is associated with CWE-648 (Incorrect Implementation of Authentication).
An authenticated, local attacker with low privileges can exploit this vulnerability by sending a crafted request to the REST API of the affected system. Successful exploitation allows the attacker to gain root privileges on the underlying operating system, potentially leading to full compromise of the SD-WAN Manager instance.
For mitigation details, refer to the Cisco Security Advisory at https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-authbp-qwCX8D4v, which was published on 2026-02-25.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-8674
Vulnerability Data
A vulnerability in Cisco Catalyst SD-WAN Manager could allow an authenticated, local attacker with low privileges to gain root privileges on the underlying operating system. This vulnerability is due to an insufficient user authentication mechanism in the REST API. An…
more
attacker could exploit this vulnerability by sending a request to the REST API of the affected system. A successful exploit could allow the attacker to gain root privileges on the underlying operating system.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
—
—
—
V3.5.2V6.4.6
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation can discover incorrect calls to privileged APIs before deployment.
Enforces authorization checks around privileged operations so that an API requiring elevated rights cannot be reached or misused without proper rights.
Least-privilege assignment directly reduces both the availability of privileged APIs and the blast radius when they are invoked incorrectly.
Security engineering principles include correct use of privileged interfaces and safe invocation patterns that stop the weakness from being introduced.
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.
Secure SDLC practices directly enforce correct usage of privileged APIs during development.
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 can detect incorrect privileged API calls but does not prevent them at design time.
Restricting privileged utility programs limits the exposure of privileged APIs to misuse.
Privileged access rights directly govern the correct use of privileged APIs and reduce misuse.
Secure development lifecycle includes API usage standards that can prevent incorrect privileged calls.
Application security requirements can specify correct invocation of privileged APIs.
Secure architecture principles guide proper privilege separation and API usage.