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IntegrityApplication · Zonelabs

CVE-2004-0309

HIGH · 10.0 CVSS v2.0 Published 2004-11-23
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
Stack-based buffer overflow in the SMTP service support in vsmon.exe in Zone Labs ZoneAlarm before 4.5.538.001, ZoneLabs Integrity client 4.0 before 4.0.146.046, and 4.5 before 4.5.085, allows remote attackers to execute arbitrary code via a long RCPT TO argument.

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

Stack-based buffer overflow in vsmon.exe SMTP service handling allows remote code execution via overly long RCPT TO commands. This vulnerability affects ZoneAlarm personal firewall and ZoneLabs Integrity client versions prior to the specified patches.

MitigationUpgrade to ZoneAlarm 4.5.538.001 or later, or ZoneLabs Integrity client 4.0.146.046/4.5.085 or later. If upgrading is not feasible, disable SMTP service monitoring in vsmon.exe or block external SMTP traffic at the perimeter.

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
IntegrityApplication
Affected:= 4.0
ZonealarmApplication
Affected:= 4.0= 4.5

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
Complete
Integrity
Complete
Availability
Complete

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

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. Locate the vsmon.exe process
    Open Task Manager or use command 'tasklist /FI "IMAGENAME eq vsmon.exe"' to find if vsmon.exe is running
    Affected if vsmon.exe is not present, the vulnerability does not apply
  2. Identify the installed product and version
    Check the installed programs list for ZoneAlarm or ZoneLabs Integrity, or right-click on the ZoneAlarm/Integrity icon in the system tray and select 'About' to view the version number
    Affected if The installed version is ZoneAlarm 4.0 or 4.5, or ZoneLabs Integrity 4.0 (prior to patches)
  3. Verify SMTP service monitoring is enabled
    Open the ZoneAlarm or Integrity client interface, navigate to the vsmon.exe or SMTP monitoring settings, and check if the SMTP service protection is turned on
    Affected if SMTP monitoring is disabled in vsmon.exe, the specific overflow condition cannot be triggered
  4. Confirm network exposure to external SMTP traffic
    Review firewall rules to determine if external port 25 (SMTP) traffic is permitted to reach the machine running vsmon.exe
    Affected if The system is not accessible via external SMTP connections, remote exploitation is not feasible

A user is affected if vsmon.exe is running with SMTP monitoring enabled on ZoneAlarm 4.0/4.5 or ZoneLabs Integrity 4.0, and the system accepts external SMTP connections.

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

Upgrade to ZoneAlarm 4.5.538.001 or later, or ZoneLabs Integrity client 4.0.146.046/4.5.085 or later. If upgrading is not feasible, disable SMTP service monitoring in vsmon.exe or block external SMTP traffic at the perimeter.

Recommended fix High confidence

ZoneAlarm 4.5.538.001+; ZoneLabs Integrity 4.0.146.046+; ZoneLabs Integrity 4.5.085+

  1. Identify the currently installed version of ZoneAlarm or ZoneLabs Integrity client
  2. For ZoneAlarm: verify if version is before 4.5.538.001 - if vulnerable, upgrade to 4.5.538.001 or later
  3. For Integrity client 4.0: verify if version is before 4.0.146.046 - if vulnerable, upgrade to 4.0.146.046 or later
  4. For Integrity client 4.5: verify if version is before 4.5.085 - if vulnerable, upgrade to 4.5.085 or later
  5. After upgrade, verify the SMTP service in vsmon.exe is no longer exposing the vulnerability
Caveat This is legacy software from 2004; upgrading may require compatibility checks with current operating systems

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

Fix this in Integrity Scoped from the published advisory
  • Consultation1.0 h
  • Implementation1.0 h
  • Testing1.0 h
  • Review / QA1.0 h
4.0 hours of engineering $750
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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-2004-0309 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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