Cyber Resilience

CVE-2026-20133

Info Disclosure in Cisco Catalyst Sd-Wan Manager ≤ 20.9.8.2

CISA KEVActive ExploitationEUVD ExploitedInfo Disclosure
Published
25 February 2026
Modified
22 April 2026
KEV Added
20 April 2026
Patch / advisory
CVSS Score v3.1 6.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.31 98th percentile
Risk Priority 76 floored blend · peak EPSS

Summary

CVE-2026-20133 is a medium-severity Exposure of Sensitive Information to an Unauthorized Actor (CWE-200) vulnerability in Cisco Catalyst Sd-Wan Manager. Its CVSS base score is 6.5 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Token Impersonation/Theft (T1134.001); ranked in the top 2% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities 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.

A vulnerability in Cisco Catalyst SD-WAN Software stems from insufficient file system restrictions and is tracked as CVE-2026-20133. The flaw carries a CVSS 3.1 score of 6.5 and is categorized under CWE-200, exposing sensitive information on the underlying operating system when triggered.

An authenticated attacker holding netadmin privileges can exploit the issue remotely by accessing the vshell on an affected device, enabling read access to sensitive files without any user interaction. The attack requires low complexity once valid credentials are obtained.

The Cisco Security Advisory cisco-sa-sdwan-authbp-qwCX8D4v and the CISA Known Exploited Vulnerabilities catalog both reference the CVE, indicating that official mitigation guidance and patching information are available through those sources.

The vulnerability appears in CISA’s KEV catalog, confirming real-world exploitation activity. Its EPSS score has remained flat at a peak and current value of 0.0202, showing no material post-disclosure increase in observed exploitation probability.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A vulnerability in Cisco Catalyst SD-WAN Software could allow an unauthenticated, remote attacker to view sensitive information on an affected system. This vulnerability is due to insufficient file system restrictions. An authenticated attacker with netadmin privileges could exploit this vulnerability…

more

by accessing the vshell of an affected system. A successful exploit could allow the attacker to read sensitive information on the underlying operating system.

CWE(s)
KEV Date Added
20 April 2026

Related Threats

MITRE ATT&CK Enterprise Techniques

T1134.001 Token Impersonation/Theft Stealth
Adversaries may duplicate then impersonate another user's existing token to escalate privileges and bypass access controls.
T1552 Unsecured Credentials Credential Access
Adversaries may search compromised systems to find and obtain insecurely stored credentials.
T1552.001 Credentials In Files Credential Access
Adversaries may search local file systems and remote file shares for files containing insecurely stored credentials.
T1552.002 Credentials in Registry Credential Access
Adversaries may search the Registry on compromised systems for insecurely stored credentials.
T1552.004 Private Keys Credential Access
Adversaries may search for private key certificate files on compromised systems for insecurely stored credentials.
T1615 Group Policy Discovery Discovery
Adversaries may gather information on Group Policy settings to identify paths for privilege escalation, security measures applied within a domain, and to discover patterns in domain objects that can be manipulated or used to blend in the…
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-20128Same product: Cisco Catalyst Sd-Wan Managerboth on KEV
CVE-2016-6415Same vendor: Ciscoboth on KEV
CVE-2026-20122Same product: Cisco Catalyst Sd-Wan Managerboth on KEV
CVE-2020-3259Same vendor: Ciscoboth on KEV
CVE-2022-20821Same vendor: Ciscoboth on KEV
CVE-2026-20262Same product: Cisco Catalyst Sd-Wan Managerboth on KEV
CVE-2025-20147Same product: Cisco Catalyst Sd-Wan Manager
CVE-2024-20475Same product: Cisco Catalyst Sd-Wan Manager
CVE-2026-20108Same product: Cisco Catalyst Sd-Wan Manager
CVE-2026-20126Same product: Cisco Catalyst Sd-Wan Manager

Affected Assets

cisco
catalyst sd-wan manager
20.12.6 · ≤ 20.9.8.2 · 20.10 — 20.12.5.3 · 20.13 — 20.15.4.2

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 7 hardening rules · 6 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V10.4.9
  • V11.7.1
  • V14.1.2
  • V14.2.4

Mitigating Controls (NIST 800-53 r5) AI

Access enforcement directly stops unauthorized actors from obtaining sensitive information.

Information flow enforcement structurally prevents sensitive data from reaching unauthorized recipients.

Protection of information at rest prevents unauthorized exposure of stored sensitive data.

Transmission confidentiality mechanisms stop exposure of sensitive data on the wire.

Least privilege reduces the set of actors who can reach sensitive information.

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.AA-05 mostly match
prevents

PR.AA-05 directly enforces least-privilege authorization that blocks most unauthorized disclosures, yet CWE-200 also arises from logging, error messages, and side-channel paths that access controls alone do not address.

PR.DS-10 mostly match
prevents

PR.DS-10 mostly prevents CWE-200 by directly eliminating unauthorized access to sensitive data-in-use, yet only partially addresses the weakness because CWE-200 spans many other exposure vectors outside runtime protection.

PR.IR-01 mostly match
prevents

PR.IR-01's segmentation/zero-trust controls largely eliminate network-level unauthorized access paths that enable exposure, yet CWE-200 spans many additional vectors (API responses, logs, app logic) that network controls alone cannot close.

PR.PS-06 mostly match
prevents

Secure SDLC practices catch most exposure flaws via design, testing and release controls, yet CWE-200 spans runtime/config issues a single development outcome cannot fully close.

PR.AA-01 partial match
prevents

PR.AA-01 supplies proper credential lifecycle controls that reduce unauthorized access paths, yet leaves many other exposure vectors (error messages, logging, side channels, etc.) unaddressed.

PR.AA-03 partial match
prevents

Authentication verifies actor identity and is a prerequisite for access decisions, yet addresses only one facet of the broad set of exposure vectors in CWE-200.

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.

prevents

Restricting anonymous or unknown access and encrypting high-value information limits the exposure of sensitive data that would otherwise be obtainable by unauthorized actors.

prevents

Suppressing system details, error specifics, and previous log-on information until successful authentication reduces the information an unauthenticated attacker can gather.

prevents

By requiring owners to assign sensitivity labels and corresponding handling rules, the control ensures that information is not left unmarked and therefore reduces the chance that sensitive data will be exposed to unauthorized actors.

prevents

Requiring encryption, access controls, and recipient authentication for transfers directly reduces the chance that sensitive data reaches an unauthorized observer.

prevents

Secure delivery, protected storage, and confidentiality of allocation records limit exposure of authentication material to unauthorized observers.

prevents

Requiring defined procedures, assigned roles, and technical/organizational measures for handling PII reduces the chance that sensitive personal data will be exposed to unauthorized actors through inadequate handling or missing safeguards.

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).

Ubuntu 22.04 (1 rule)
  • V-260470 Ubuntu 22.04 LTS, when booted, must require authentication upon booting into single-user and maintenance modes. prevents CWE-200
Ubuntu 24.04 (2 rules)
  • V-270647 Ubuntu 24.04 LTS must not have the telnet package installed. prevents CWE-200
  • V-270675 Ubuntu 24.04 LTS when booted must require authentication upon booting into single-user and maintenance modes. prevents CWE-200
Windows 10 (1 rule)
  • V-220737 Administrative accounts must not be used with applications that access the Internet, such as web browsers, or with potential Internet sources, such as email. prevents CWE-200
Windows Server 2016 (1 rule)
  • V-224974 Domain-created Active Directory Organizational Unit (OU) objects must have proper access control permissions. prevents CWE-200
Windows Server 2019 (1 rule)
  • V-205743 Windows Server 2019 organization created Active Directory Organizational Unit (OU) objects must have proper access control permissions. prevents CWE-200
Windows Server 2022 (1 rule)
  • V-254395 Windows Server 2022 organization created Active Directory Organizational Unit (OU) objects must have proper access control permissions. prevents CWE-200

References