Firewall CommunityApplication · Endian

CVE-2026-34818

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 remark parameter to /manage/dnsmasq/localdomains/. 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 /manage/dnsmasq/localdomains/ endpoint. The 'remark' parameter accepts unsanitized user input, allowing an authenticated attacker to inject malicious JavaScript that persists on the page and executes in the browsers of other users who view the affected interface.

MitigationImplement output encoding and input validation/sanitization on the remark parameter to neutralize HTML/JavaScript payloads before storage and display. If a patched version is available, upgrade to a version beyond 3.3.25.

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. Identify Endian Firewall installation
    Confirm the target system is running Endian Firewall. This is typically a dedicated network appliance or Linux-based system with the Endian web interface accessible on port 443 or 10443.
    Affected if The system is running Endian Firewall Community edition web interface.
  2. Check installed version
    Log into the Endian Firewall web UI and navigate to the System > Status page, or run the command 'cat /etc/e-smith-release' via SSH to retrieve the exact version number. Compare against 3.3.25.
    Affected if The installed version is 3.3.25 or any version prior to 3.3.25.
  3. Verify dnsmasq module is enabled
    Access the web UI and navigate to the DNSmasq section under Services, or inspect the configuration file /var/tmp/e-smith/db/dnsmasq/ configuration to confirm the DNSmasq service is active.
    Affected if The DNSmasq service is enabled and the local domains management interface is accessible.
  4. Confirm vulnerable endpoint is accessible
    Attempt to access the URL path /manage/dnsmasq/localdomains/ via the web browser while authenticated. If the page loads with a form containing a 'remark' or comment field, the endpoint is present.
    Affected if The /manage/dnsmasq/localdomains/ endpoint is accessible and displays a form with an input field for remarks or comments.

A system is affected if it runs Endian Firewall Community version 3.3.25 or lower, has the DNSmasq service enabled, and exposes the web management interface with access to the local domains configuration page.

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 output encoding and input validation/sanitization on the remark parameter to neutralize HTML/JavaScript payloads before storage and display. If a patched version is available, upgrade to a version beyond 3.3.25.

Fix this in Firewall Community Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,040
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An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,664.

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-2026-34818 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
  • No spam, self-promotion, credentials, or personal data