dbcve.org
FreshtomatoOperating system

CVE-2023-3991

CRITICAL · 9.8 CVSS v3.1 Published 2023-10-16
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

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
An OS command injection vulnerability exists in the httpd iperfrun.cgi functionality of FreshTomato 2023.3. A specially crafted HTTP request can lead to arbitrary command execution. An attacker can send an HTTP request to trigger this vulnerability.

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

OS command injection vulnerability in FreshTomato 2023.3 firmware's httpd web server, specifically in the iperfrun.cgi component. Attackers can achieve arbitrary command execution by sending specially crafted HTTP requests due to insufficient input validation allowing shell metacharacter injection.

MitigationApply vendor patches when available; temporarily restrict access to the administrative web interface to trusted IPs only; disable iperf functionality if not required.

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
FreshtomatoOperating system
Affected:= 2023.3

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
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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 FreshTomato firmware version
    Access the router's web interface and navigate to Administration > System or check via command line using 'nvram get os_version' or 'grep version /etc/freshtomato_user_config'
    Affected if The installed version is exactly 2023.3 (this specific version is affected)
  2. Verify iperfrun.cgi is present
    Check if the file exists on the router filesystem at /www/iperfrun.cgi or attempt to access it via HTTP at http://<router-ip>/iperfrun.cgi
    Affected if The iperfrun.cgi script exists and responds to requests (the vulnerable component is present)
  3. Confirm iperf functionality is enabled
    Check router configuration for iperf server settings or examine if the iperf-related features are active in the web interface under Advanced > Bandwidth/iperf settings
    Affected if The iperf server/functionality is enabled (the attack surface is active)
  4. Assess web interface exposure
    Determine if the router's HTTP/HTTPS web interface (port 80/443) is accessible from untrusted networks by checking router firewall rules and port forwarding configurations
    Affected if The administrative web interface is accessible from outside the trusted network (attackers can reach the vulnerable component)

A system is affected if it runs FreshTomato 2023.3, has iperfrun.cgi accessible, and has the administrative web interface exposed to untrusted networks.

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.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply vendor patches when available; temporarily restrict access to the administrative web interface to trusted IPs only; disable iperf functionality if not required.

Recommended fix Moderate confidence

Latest FreshTomato release newer than 2023.3 (check official FreshTomato sources for version containing the CVE-2023-3991 fix)

  1. 1. Navigate to the FreshTomato official download page or GitHub repository
  2. 2. Identify the latest stable FreshTomato release version that is newer than 2023.3
  3. 3. Download the firmware file appropriate for your specific router model
  4. 4. Access your router's web administration interface
  5. 5. Navigate to the Administration > Firmware Upgrade section
  6. 6. Upload and apply the new firmware version
  7. 7. After the router restarts, verify the new firmware version is installed
Caveat Router firmware upgrades may reset configuration to defaults; backup current settings before upgrading

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Freshtomato Scoped from the published advisory
  • Consultation6.0 h
  • Implementation8.0 h
  • Testing8.0 h
  • Review / QA4.0 h
26.0 hours of engineering $4,560
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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-2023-3991 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