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RancherApplication · Suse

CVE-2021-25313

MEDIUM · 6.1 CVSS v3.1 Published 2021-03-05
Fix available
A fix is available. Upgrade to 2.5.6 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
A Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Rancher allows remote attackers to execute JavaScript via malicious links. This issue affects: SUSE Rancher Rancher versions prior to 2.5.6.

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

A stored Cross-site Scripting (XSS) vulnerability in SUSE Rancher allows remote attackers to inject malicious JavaScript via crafted links that are rendered without proper input sanitization during web page generation. The vulnerability stems from improper neutralization of user-supplied input in the web interface.

MitigationUpgrade Rancher to version 2.5.6 or later. If immediate upgrade is not feasible, implement Content Security Policy (CSP) headers and input validation on the web interface as compensating controls.

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
RancherApplication
Affected:< 2.5.6

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 Rancher version
    Access the Rancher UI and navigate to the About page (click your user profile > About), or run 'kubectl get rancher --namespace cattle-system' to retrieve the version via CLI
    Affected if The displayed version is earlier than 2.5.6 (for example, 2.5.0 through 2.5.5)
  2. Confirm web interface is accessible
    Verify that the Rancher web UI is running and accessible at your Rancher URL
    Affected if The web interface is enabled and reachable, exposing the user-supplied input rendering surface
  3. Locate user-supplied input fields in UI
    Examine Rancher UI components where users can input custom data, such as project names, cluster descriptions, or user profile fields
    Affected if Custom user input can be entered into web interface fields that are later displayed back to users without sanitization

You are affected if your Rancher version is below 2.5.6 and the web interface is accessible, as the stored XSS vulnerability exists in how user-supplied input is rendered without sanitization.

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 2.5.6 or later
Fixed in 2.5.6
Interim mitigation

Upgrade Rancher to version 2.5.6 or later. If immediate upgrade is not feasible, implement Content Security Policy (CSP) headers and input validation on the web interface as compensating controls.

Fix this in Rancher Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing4.0 h
  • Review / QA2.0 h
18.0 hours of engineering $3,200
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Scan for this in your stack

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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-2021-25313 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
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data