Catalyst Sd Wan ManagerApplication · Cisco
CVE-2026-20210
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedA vulnerability in the web UI of Cisco Catalyst SD-WAN Manager, formerly SD-WAN vManage, could allow an authenticated, remote attacker with read-only permissions to modify configurations and perform unauthorized actions on an affected system. This vulnerability exists because of a failure to redact sensitive information within device configurations and templates. An attacker could exploit this vulnerability by elevating their read-only permissions to those of a high-privileged user. A successful exploit could allow the attacker to access or modify configuration settings within Cisco Catalyst SD-WAN Manager as a high-privileged user.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · moderate confidenceVulnerability in Cisco Catalyst SD-WAN Manager web UI allows authenticated read-only users to elevate privileges to high-privileged users by exploiting failure to redact sensitive information in device configurations and templates, enabling unauthorized modification of system settings.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
Catalyst Sd Wan ManagerApplication
< 20.9.9.1>= 20.10, < 20.12.5.4>= 20.12.6, < 20.12.6.2>= 20.13, < 20.15.4.4>= 20.15.5, < 20.15.5.2>= 20.16, < 20.18.2.2>= 26.1, < 26.1.1.1= 20.12.7CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify Cisco Catalyst SD-WAN Manager versionAccess the web UI and navigate to Administration > System Settings > Software Updates or use the CLI command 'show version' on the SD-WAN Manager device to retrieve the installed software version.Affected if The installed version falls within any of the following ranges: < 20.9.9.1; >= 20.10 and < 20.12.5.4; >= 20.12.6 and < 20.12.6.2; >= 20.13 and < 20.15.4.4; >= 20.15.5 and < 20.15.5.2; >= 20.16 and < 20.18.2.2; >= 26.1 and < 26.1.1.1; or exactly version 20.12.7.
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Verify presence of read-only user accountsIn the web UI, navigate to Administration > User Administration > Users or use the API endpoint to list all user accounts and their assigned roles. Look for users with 'read-only' or 'viewer' role assignments.Affected if Any read-only or viewer-role user accounts exist in the system.
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Inspect device configuration templates for sensitive data exposureIn the web UI, go to Configuration > Templates > Device Templates. Create a new template or view an existing one and examine the configuration output. Check whether sensitive fields such as passwords, secrets, keys, or authentication tokens are visible in plain text rather than masked or redacted.Affected if Sensitive information such as passwords, PSKs, or API keys are displayed in plain text or are viewable by read-only users in device configurations or templates.
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Check privilege escalation capability via web UILog in with a read-only user account. Navigate to sections that should be restricted, such as Administration > User Administration, Configuration > Templates > Device Templates edit functions, or any system settings modification areas. Attempt to access or modify settings that should require elevated privileges.Affected if A read-only user can access, view, or modify configuration templates, user settings, or system parameters that should be restricted to administrative users.
Your environment is affected if the installed Cisco Catalyst SD-WAN Manager version matches the vulnerable ranges AND read-only users exist who can view unredacted sensitive information in device configurations or templates, enabling potential privilege escalation.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped20.9.9.120.12.5.420.12.6.2
Apply Cisco's vendor patch for CVE-2026-20210 and review user permission configurations to ensure proper separation between read-only and privileged roles.
Cisco Catalyst SD-WAN Manager 20.15.4.4 or later (or the appropriate fixed version within your release train: 20.9.9.1+, 20.12.5.4+, or 20.12.6.2+)
- 1. Identify the current installed version of Cisco Catalyst SD-WAN Manager using the web UI or CLI
- 2. Determine the appropriate upgrade path based on current version - for versions below 20.9.9.1, upgrade to 20.9.9.1 or later; for 20.10.x, upgrade to 20.12.5.4 or later; for 20.12.6.x, upgrade to 20.12.6.2 or later; for 20.13.x through 20.15.4.3, upgrade to 20.15.4.4 or later
- 3. Review Cisco SD-WAN Manager upgrade documentation and release notes for compatibility requirements
- 4. Take a full backup of the current configuration before upgrading
- 5. Perform the upgrade following Cisco's standard upgrade procedure for SD-WAN Manager
- 6. After upgrade, verify the system is operational and test that the vulnerability is remediated
- 7. Confirm the new version is no longer in the affected ranges listed
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Catalyst Sd Wan Manager
Scoped from the published advisory
- Consultation3.0 h
- Implementation4.0 h
- Testing3.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,408.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-20210 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-20210 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
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