Exchange ServerApplication · Microsoft

CVE-2000-0216

MEDIUM · 5.0 CVSS v2.0 Published 2000-02-29
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
Microsoft email clients in Outlook, Exchange, and Windows Messaging automatically respond to Read Receipt and Delivery Receipt tags, which could allow an attacker to flood a mail system with responses by forging a Read Receipt request that is redirected to a large distribution list.

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

Microsoft Outlook, Exchange, and Windows Messaging email clients automatically generate and send Read Receipt and Delivery Receipt responses when prompted by incoming email headers. An attacker can exploit this by crafting a forged email with a receipt request directed at a large distribution list, causing the mail system to flood the target with automated responses.

MitigationDisable automatic Read Receipt and Delivery Receipt processing in Outlook client settings and configure Exchange server rules to strip or quarantine external receipt requests before delivery to internal distribution lists.

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
Exchange ServerApplication
Affected:all versions
OutlookApplication
Affected:all versions
Windows MessagingApplication
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
None
Integrity
None
Availability
Partial

AV:N/AC:L/Au:N/C:N/I:N/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. Check Outlook automatic receipt settings
    In Outlook, go to Options > Email > Tracking and verify if 'Send read receipt' or 'Send delivery receipt' options are enabled for incoming messages.
    Affected if Automatic read or delivery receipt processing is enabled in Outlook client settings
  2. Check Exchange server receipt handling configuration
    Inspect Exchange transport rules or routing configuration for any rules that automatically process incoming receipt requests. Look for settings related to DSN (Delivery Status Notification) handling.
    Affected if Exchange is configured to automatically process and respond to receipt requests without filtering external sources
  3. Check Windows Messaging receipt settings
    Examine Windows Messaging client options for automatic receipt generation settings. Look under message handling or receipt configuration areas.
    Affected if Windows Messaging is set to automatically send read or delivery receipts in response to incoming requests
  4. Verify installed product versions
    Check installed versions of Microsoft Outlook, Exchange Server, and Windows Messaging against the affected ranges (all versions). Use 'winver' for Windows components or check Program Files for Outlook, and Exchange Administrator or Get-ExchangeServer for Exchange.
    Affected if Any affected product (Outlook, Exchange Server, or Windows Messaging) is installed regardless of version, as all versions are impacted

If automatic receipt processing is enabled on any affected email client (Outlook or Windows Messaging) or Exchange server, the environment is vulnerable to receipt flood attacks via forged receipt request headers.

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

Disable automatic Read Receipt and Delivery Receipt processing in Outlook client settings and configure Exchange server rules to strip or quarantine external receipt requests before delivery to internal distribution lists.

Fix this in Exchange Server 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

Check whether your project pulls in CVE-2000-0216 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

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-2000-0216 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