CommunicatorApplication · Netscape

CVE-2000-0087

MEDIUM · 5.0 CVSS v2.0 Published 2000-01-12
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
59/100
Remediation priority · Elevated
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
Netscape Mail Notification (nsnotify) utility in Netscape Communicator uses IMAP without SSL, even if the user has set a preference for Communicator to use an SSL connection, allowing a remote attacker to sniff usernames and passwords in plaintext.

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

The Netscape Mail Notification (nsnotify) utility in Netscape Communicator uses IMAP protocol without SSL encryption, disregarding user-set preferences for SSL connections. This allows remote attackers on the same network segment to intercept and sniff IMAP authentication credentials (usernames and passwords) in plaintext.

MitigationThis vulnerability affects legacy Netscape Communicator software which is long deprecated. The primary remediation is to discontinue use of the vulnerable nsnotify utility and migrate to modern, secure mail clients that support encrypted IMAPS connections. Network segmentation or VPN usage can provide additional protection for any remaining legacy systems.

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
CommunicatorApplication
Affected:= 4.7
NavigatorApplication
Affected:all versions

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
None
Availability
None

AV:N/AC:L/Au:N/C:P/I:N/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. Verify Netscape Communicator or Navigator installation
    Search for Netscape executables (netscape.exe, communicator.exe) in common installation directories such as C:\Program Files\Netscape or C:\Netscape, or check system registry for Netscape components under HKEY_LOCAL_MACHINE\SOFTWARE\Netscape
    Affected if Netscape Communicator 4.7 or any Netscape Navigator version is installed on the system
  2. Locate nsnotify utility
    Search for nsnotify.exe or nsnotify.dll in the Netscape installation directory, typically under the Communicator\Program or Navigator\Program folders
    Affected if The nsnotify utility binary is present on the system
  3. Check IMAP notification configuration
    Examine Netscape preference files (prefs.js, pref.js) in the user profile directory for settings containing 'nsnotify', 'mail.server', or 'imap' configuration entries; look for 'socket.security' or 'ssl' settings set to false or 0
    Affected if nsnotify is configured to check IMAP mail and SSL is disabled or not enforced in the configuration
  4. Inspect network traffic patterns
    Use network monitoring tools (such as Wireshark or netstat) to capture traffic on port 143 (IMAP) while nsnotify is active; check if plaintext IMAP authentication is transmitted without TLS/SSL encapsulation
    Affected if Plaintext IMAP authentication traffic on port 143 is observed from the Netscape client

A user is affected if Netscape Communicator or Navigator with the nsnotify utility is installed and configured to monitor IMAP mail without SSL/TLS encryption enabled.

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

This vulnerability affects legacy Netscape Communicator software which is long deprecated. The primary remediation is to discontinue use of the vulnerable nsnotify utility and migrate to modern, secure mail clients that support encrypted IMAPS connections. Network segmentation or VPN usage can provide additional protection for any remaining legacy systems.

Fix this in Communicator Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA1.0 h
9.0 hours of engineering $1,600
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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-2000-0087 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