dbcve.org
Data Center Network ManagerApplication · Cisco

CVE-2021-1286

MEDIUM · 6.1 CVSS v3.1 Published 2021-01-20
Fix available
A fix is available. Upgrade to 11.5 or later.
See remediation →
68/100
Remediation priority · Elevated
Remotely reachable No privileges

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 the web-based management interface of Cisco Data Center Network Manager (DCNM) could allow a remote attacker with network-operator privileges to conduct a cross-site scripting (XSS) attack or a reflected file download (RFD) attack against a user of the interface. 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 · high confidence

Multiple cross-site scripting (XSS) and reflected file download (RFD) vulnerabilities exist in the web-based management interface of Cisco Data Center Network Manager (DCNM). An authenticated remote attacker with network-operator privileges can craft malicious requests that execute in the context of other users' sessions, potentially stealing session data or downloading malicious files.

MitigationApply the vendor-provided patches for Cisco DCNM. If patches are unavailable, restrict access to the web management interface to trusted networks only and implement strict Content Security Policy (CSP) headers to mitigate XSS attacks.

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
Data Center Network ManagerApplication
Affected:< 11.5\(1\)

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
Network
Complexity
Low
Privileges
None
User interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/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 checks

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

  1. Identify the installed DCNM version
    Access the Cisco DCNM web interface and navigate to the About or Administration > System Settings > Servers page to view the version number. Alternatively, log into the DCNM server via SSH and run the command 'dcnmrepow --version' or check the installer log files in /var/log/cisco/dcnm/
    Affected if The installed version is lower than 11.5(1)
  2. Confirm the web-based management interface is active
    Verify that the DCNM web service is running by accessing the management interface URL (typically https://<dcnm-ip>) or by checking the service status via SSH with 'show system services' or by reviewing running processes for 'jboss' or 'tomcat'
    Affected if The web management interface is accessible and responding to requests
  3. Check for existing network-operator accounts
    In the DCNM web interface, go to Administration > Users and Roles > User Management to enumerate accounts with the network-operator role. Alternatively, query the DCNM database or use the CLI command 'dcnm-show-user -a' to list assigned roles
    Affected if Any network-operator accounts exist in the system, creating a potential attack vector for authenticated exploitation
  4. Review server logs for indicators of XSS or RFD attacks
    Examine DCNM server logs in /var/log/cisco/dcnm/ for suspicious request patterns, particularly any unusual URL parameters, script tags, or file download attempts. Search for entries containing '<script>', 'javascript:', or unexpected 'Content-Disposition' headers
    Affected if Logs contain evidence of malicious request patterns targeting the web interface

A user is affected if their DCNM installation is version 11.4(1) or earlier AND the web-based management interface is accessible with network-operator accounts present.

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
Upgrade available Upgrade to 11.5 or later
Fixed in 11.5
Interim mitigation

Apply the vendor-provided patches for Cisco DCNM. If patches are unavailable, restrict access to the web management interface to trusted networks only and implement strict Content Security Policy (CSP) headers to mitigate XSS attacks.

Fix this in Data Center Network Manager Scoped from the published advisory
  • Consultation3.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA2.0 h
12.0 hours of engineering $2,130
Get the upgrade done

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 locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-1286 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2021-1286 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data