dbcve.org
Sd Wan FirmwareOperating system · Cisco

CVE-2021-1261

HIGH · 7.8 CVSS v3.1 Published 2021-01-20
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
80/100
Remediation priority · High
Zero-click

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 · unedited
Multiple vulnerabilities in Cisco SD-WAN products could allow an authenticated attacker to perform command injection attacks against an affected device, which could allow the attacker to take certain actions with root privileges on the device. For more information about these vulnerabilities, see the Details section of this advisory.

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 confidence

Multiple command injection vulnerabilities in Cisco SD-WAN products allow an authenticated attacker to execute arbitrary commands with root privileges on affected devices. These vulnerabilities stem from insufficient input validation in the SD-WAN software, enabling attackers to escape intended command boundaries.

MitigationApply Cisco-provided patches for the SD-WAN vulnerabilities. Restrict administrative access to trusted personnel and monitor for unauthorized root-level command execution.

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
Sd Wan FirmwareOperating system
Affected:= 18.2.0= 18.3.0= 18.3.8= 18.4.6= 19.2.3= 19.2.99= 20.1.0
Sd Wan Vsmart Controller FirmwareOperating system
Affected:all versions
Catalyst Sd Wan ManagerApplication
Affected:all versions
Sd Wan Vbond OrchestratorApplication
Affected:all versions

CVSS 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
Local
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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 checks

Work through these to decide whether this CVE applies to you.

  1. Identify the installed SD-WAN component
    Run 'show version' on the device CLI or check the vManage/vSmart/vBond administration interface to determine which SD-WAN software component is running
    Affected if The device is running Cisco SD-WAN Firmware, vSmart Controller, Catalyst SD-WAN Manager, or vBond Orchestrator
  2. Determine the firmware or software version
    Use the CLI command 'show version' or access the web UI System Information page to read the exact version number installed
    Affected if The installed version is 18.2.0, 18.3.0, 18.3.8, 18.4.6, 19.2.3, 19.2.99, or 20.1.0 for SD-WAN Firmware, or any version for vSmart Controller, Catalyst SD-WAN Manager, or vBond Orchestrator
  3. Verify if the SD-WAN management interface is accessible
    Check if TCP ports 443, 8443, or 22 (for web UI or CLI) are open and reachable from untrusted networks using 'show interfaces' or network scanning tools
    Affected if The SD-WAN management interface is exposed to networks outside the trusted administrative zone
  4. Review authentication configuration
    Execute 'show running-config | include username' in CLI or check Local User Management in vManage to list all administrative accounts
    Affected if There are unexpected or unauthorized user accounts configured in the system
  5. Check for evidence of command injection
    Review system logs in /var/log/ or via 'show logging' for suspicious command patterns, unexpected shell spawns, or root-level command execution from administrative sessions
    Affected if Logs contain commands or shell invocations that were not initiated by legitimate administrators

You are affected if you run any SD-WAN component (vSmart, vManage, vBond, or the listed firmware versions) with its management interface accessible to authenticated users.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply Cisco-provided patches for the SD-WAN vulnerabilities. Restrict administrative access to trusted personnel and monitor for unauthorized root-level command execution.

Fix this in Sd Wan Firmware Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,860
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-1261 in production — separate from our analysis above.

No notes yet

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What this is

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.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
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  • No spam, self-promotion, credentials, or personal data