dbcve.org
FortiosOperating system · Fortinet

CVE-2017-7733

MEDIUM · 6.1 CVSS v3.0 Published 2017-10-27
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
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 Cross-Site-Scripting (XSS) vulnerability in Fortinet FortiOS 5.4.0 to 5.4.5 and 5.6.0 allows a remote unauthenticated attacker to execute arbitrary javascript code via webUI "Login Disclaimer" redir parameter.

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

Cross-Site-Scripting (XSS) vulnerability in Fortinet FortiOS webUI allows remote unauthenticated attackers to execute arbitrary JavaScript code via the Login Disclaimer redir parameter in versions 5.4.0-5.4.5 and 5.6.0.

MitigationUpgrade FortiOS to a patched version that addresses this vulnerability; apply input validation/sanitization to the redir parameter in the Login Disclaimer feature.

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
FortiosOperating system
Affected:= 5.4.0= 5.4.1= 5.4.2= 5.4.3= 5.4.4= 5.4.5= 5.6.0

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:3.0/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. Determine FortiOS version
    Run 'get system status' via CLI or check System > Firmware in webUI to identify the installed FortiOS version
    Affected if Version is 5.4.0, 5.4.1, 5.4.2, 5.4.3, 5.4.4, 5.4.5, or 5.6.0
  2. Confirm Login Disclaimer is enabled
    Navigate to System > Administration > Login Disclaimer in the webUI, or run 'get system interface' and check for disclaimer configuration via CLI
    Affected if Login Disclaimer feature is configured and active on the login page
  3. Verify webUI is exposed
    Check network configuration to confirm the FortiOS webUI (port 443 or 80) is accessible from untrusted networks, or review firewall policies allowing external access to the administrative interface
    Affected if WebUI is reachable from unauthenticated remote attackers

You are affected if your FortiOS version is exactly 5.4.0 through 5.4.5 or 5.6.0 AND the Login Disclaimer feature is enabled AND the webUI is externally accessible.

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

Upgrade FortiOS to a patched version that addresses this vulnerability; apply input validation/sanitization to the redir parameter in the Login Disclaimer feature.

Fix this in Fortios 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 help mitigating

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-2017-7733 — 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-2017-7733 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