Firewall CommunityApplication · Endian

CVE-2026-34812

MEDIUM · 5.4 CVSS v3.1 Published 2026-04-02
Fix available
A fix is available. Upgrade to after 3.3.25 or later.
See remediation →
58/100
Remediation priority · Elevated
Remotely reachable

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
Endian Firewall version 3.3.25 and prior allow stored cross-site scripting (XSS) via the mimetypes parameter to /cgi-bin/proxypolicy.cgi. An authenticated attacker can inject arbitrary JavaScript that is stored and executed when other users view the affected page.

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

Endian Firewall 3.3.25 and prior contains a stored XSS vulnerability in the proxy policy management interface. The mimetypes parameter in /cgi-bin/proxypolicy.cgi does not properly sanitize user input, allowing an authenticated attacker to inject malicious JavaScript that persists and executes when other users access the affected page.

MitigationImplement proper input validation and output encoding for the mimetypes parameter. Use context-appropriate escaping when the parameter value is rendered in HTML, or employ a web application firewall as a compensating control until the code fix is deployed.

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
Firewall CommunityApplication
Affected:<= 3.3.25

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
Low
User interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:L/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. Confirm Endian Firewall Community is installed
    Check the system version by accessing the web interface login page, or run 'cat /etc/e-smith-release' or 'rpm -q endian-firewall' on the console to identify the installed version number
    Affected if The installed version is Endian Firewall Community 3.3.25 or any prior version (3.x series)
  2. Verify the proxy web interface is accessible
    Attempt to access https://[your-firewall-ip]/cgi-bin/proxypolicy.cgi or check if port 443/80 is open and responding for the proxy policy configuration pages
    Affected if The web interface is accessible and the proxypolicy.cgi script exists and responds to requests
  3. Locate the mimetypes parameter in proxy policy configuration
    Navigate to the Proxy settings in the web interface (Proxy > Policy or similar), or inspect the HTML source of the proxypolicy.cgi page to find form fields containing 'mimetypes' as a parameter name
    Affected if The proxy policy configuration page contains a mimetypes input field that accepts user-supplied values
  4. Check for existing XSS payloads in stored mimetypes data
    Examine the proxy policy configuration for any pre-existing mimetype entries that contain HTML tags such as <script>, <img>, or javascript: URIs, or view the page source to detect encoded XSS patterns
    Affected if The mimetypes field contains unsanitized HTML/JavaScript that would execute when the page is viewed by other users

You are affected if you are running Endian Firewall Community version 3.3.25 or prior, the web interface is accessible, and the proxy policy configuration contains unsanitized user input in the mimetypes parameter.

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 a release after 3.3.25
Interim mitigation

Implement proper input validation and output encoding for the mimetypes parameter. Use context-appropriate escaping when the parameter value is rendered in HTML, or employ a web application firewall as a compensating control until the code fix is deployed.

Fix this in Firewall Community Scoped from the published advisory
  • Consultation2.0 h
  • Implementation3.0 h
  • Testing2.0 h
  • Review / QA1.0 h
8.0 hours of engineering $1,420
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Scan for this in your stack

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dbcve dependency scanner

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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-2026-34812 in production — separate from our analysis above.

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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
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