Cyber Resilience

CVE-2026-20128

Cisco Catalyst Sd-Wan Manager ≤ 20.9.8.2

CISA KEVActive ExploitationEUVD Exploited
Published
25 February 2026
Modified
21 April 2026
Patch / advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.069 94th percentile
Risk Priority 78 floored blend · peak EPSS

Summary

CVE-2026-20128 is a high-severity Storing Passwords in a Recoverable Format (CWE-257) vulnerability in Cisco Catalyst Sd-Wan Manager. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Group Policy Preferences (T1552.006); ranked in the top 6% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.

The strongest mitigations our analysis identified map to IA-5 (Authenticator Management) — 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 the Data Collection Agent (DCA) feature of Cisco Catalyst SD-WAN Manager stems from the presence of a credential file containing the DCA user password on affected systems. The flaw, tracked as CVE-2026-20128 and assigned CWE-257, enables an attacker to retrieve the stored password and is present in releases prior to 20.18.

An unauthenticated remote attacker can exploit the issue by sending a crafted HTTP request that exposes the credential file, thereby obtaining DCA user privileges on the target system and potentially pivoting to additional affected devices. The CVSS 3.1 score of 7.5 reflects high impact on confidentiality, integrity, and availability under local access conditions with high attack complexity.

Cisco's security advisory states that versions 20.18 and later are unaffected, while the vulnerability appears in CISA's Known Exploited Vulnerabilities catalog. The current EPSS score of 0.0008 indicates low exploitation probability at the time of reporting.

EU & UK References

Vulnerability Data

A vulnerability in the Data Collection Agent (DCA) feature of Cisco Catalyst SD-WAN Manager could allow an unauthenticated, remote attacker to gain DCA user privileges on an affected system. This vulnerability is due to the presence of a credential file…

more

for the DCA user on an affected system. An attacker could exploit this vulnerability by sending a crafted HTTP request and reading the file that contains the DCA password from that affected system. A successful exploit could allow the attacker to access another affected system and gain DCA user privileges. Note: Cisco Catalyst SD-WAN Manager releases 20.18 and later are not affected by this vulnerability.

CWE(s)
KEV Date Added
See CISA KEV catalog

Related Threats

MITRE ATT&CK Enterprise Techniques

T1552.006 Group Policy Preferences Credential Access
Adversaries may attempt to find unsecured credentials in Group Policy Preferences (GPP).
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.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-20133Same product: Cisco Catalyst Sd-Wan Managerboth on KEV
CVE-2026-20262Same product: Cisco Catalyst Sd-Wan Managerboth on KEV
CVE-2026-20122Same product: Cisco Catalyst Sd-Wan Managerboth on KEV
CVE-2026-20126Same product: Cisco Catalyst Sd-Wan Manager
CVE-2026-20129Same product: Cisco Catalyst Sd-Wan Manager
CVE-2026-20210Same product: Cisco Catalyst Sd-Wan Manager
CVE-2024-20475Same product: Cisco Catalyst Sd-Wan Manager
CVE-2025-20147Same product: Cisco Catalyst Sd-Wan Manager
CVE-2025-20157Same product: Cisco Catalyst Sd-Wan Manager
CVE-2025-20187Same 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)

Validate
Prove the fix (OWASP ASVS)
  • V11.4.2
  • V11.4.4

Mitigating Controls (NIST 800-53 r5) AI

IA-5 requires proper management of authenticators including storage of passwords only in non-recoverable (hashed) form, directly stopping the weakness from existing.

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.DS-01 mostly match
prevents

Protecting data-at-rest with cryptographic hashes directly prevents recoverable password storage.

PR.PS-06 partial match
prevents

Secure SDLC practices include requirements for non-recoverable password storage.

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.

degrades

Directly requires secure handling and protection of authentication information, preventing storage in recoverable formats.

degrades

Mandates secure authentication mechanisms that preclude recoverable password storage.

degrades

Requires proper use of cryptography, which can mitigate recoverable storage if applied correctly to passwords.

prevents

Secure SDLC includes requirements that reduce the likelihood of introducing recoverable password storage.

prevents

Secure coding practices can prevent developers from implementing recoverable password storage.

References