Firewall 1Application · Checkpoint

CVE-2000-0805

HIGH · 7.5 CVSS v2.0 Published 2000-11-14
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
84/100
Remediation priority · High
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
Check Point VPN-1/FireWall-1 4.1 and earlier improperly retransmits encapsulated FWS packets, even if they do not come from a valid FWZ client, aka "Retransmission of Encapsulated Packets."

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

Check Point VPN-1/FireWall-1 4.1 and earlier improperly retransmits encapsulated FWS (FWZ) packets even when they originate from invalid or non-existent FWZ clients. This allows an attacker to potentially inject malicious encapsulated traffic that the firewall will blindly forward, enabling packet injection or manipulation attacks.

MitigationUpgrade to Check Point VPN-1/FireWall-1 version 4.1 SP2 or later, or migrate to a supported Check Point security gateway version. If upgrading is not feasible, restrict FWZ/encapsulated traffic at network boundaries using additional filtering.

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 1Application
Affected:= 3.0= 4.0= 4.1

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
Authentication
None
Confidentiality
Partial
Integrity
Partial
Availability
Partial

AV:N/AC:L/Au:N/C:P/I:P/A:P

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 Check Point Firewall-1 installation
    Locate Check Point Firewall-1/VPN-1 installation directories (typically under /opt/Checkpoint or C:\Program Files\CheckPoint\FW1) or check for fw process running on the system
    Affected if Check Point Firewall-1 is installed on the system
  2. Determine installed Firewall-1 version
    Use Check Point command-line tools (fw ver -k or cpconfig) or inspect version information in the installation directory to obtain the exact version number
    Affected if Version is 3.0, 4.0, or 4.1 (any version at or below 4.1)
  3. Verify FWZ encapsulation feature status
    Examine Firewall-1 policy or configuration for FWZ-related rules, VPN communities, or encapsulated traffic settings. Check if FWZ (FWZ1) protocol is defined in the rulebase or enabled in VPN configuration
    Affected if FWZ/encapsulated traffic handling is enabled in the firewall policy
  4. Inspect FWZ packet handling configuration
    Review firewall logs and configuration for any settings related to packet retransmission, encapsulated client validation, or FWZ peer handling. Look for 'FWZ' or 'encapsulation' keywords in policy files
    Affected if Firewall is configured to handle FWZ encapsulated packets without strict client validation
  5. Check network interface configuration for FWZ traffic
    Monitor network interfaces or capture traffic to identify if FWZ-encapsulated packets are being processed. Review FWZ-related service definitions in the firewall rulebase
    Affected if The firewall is actively processing or forwarding FWZ-encapsulated traffic

A system is affected if it runs Check Point Firewall-1 version 3.0, 4.0, or 4.1 and has FWZ encapsulation feature enabled in its configuration.

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 to Check Point VPN-1/FireWall-1 version 4.1 SP2 or later, or migrate to a supported Check Point security gateway version. If upgrading is not feasible, restrict FWZ/encapsulated traffic at network boundaries using additional filtering.

Fix this in Firewall 1 Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA2.0 h
20.0 hours of engineering $3,500
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Scan for this in your stack

Free · runs locally
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-2000-0805 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