OpenBSDOperating system

CVE-2000-0310

MEDIUM · 5.0 CVSS v2.0 Published 2001-03-12
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
IP fragment assembly in OpenBSD 2.4 allows a remote attacker to cause a denial of service by sending a large number of fragmented 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 · high confidence

OpenBSD 2.4 contains a vulnerability in its IP fragment assembly code where a remote attacker can cause a denial of service by sending a large number of fragmented IP packets, likely exhausting memory or processing resources during reassembly.

MitigationSince OpenBSD 2.4 is extremely outdated (released 1998), the primary remediation is to upgrade to a supported OpenBSD version. Alternatively, implement edge filtering to block or rate-limit fragmented packets at network perimeter devices.

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
OpenBSDOperating system
Affected:= 2.4

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. Verify OpenBSD version
    Run `uname -a` or check the contents of `/etc/motd` to identify the installed OpenBSD version number
    Affected if The version displayed is exactly 2.4
  2. Confirm IP networking is enabled
    Check if the system has IP networking active by running `ifconfig -a` to list network interfaces
    Affected if Any network interface shows an IP address, indicating the system is processing IP traffic including fragments
  3. Check kernel fragment handling
    Inspect running network statistics with `netstat -s -p ip` to see if IP fragment reassembly is occurring
    Affected if Fragment-related counters are present and incrementing, confirming the vulnerable reassembly code path is in use
  4. Look for exploitation symptoms
    Run `vmstat 1` and `ps aux` to check for unusually high memory usage or CPU consumption that could indicate fragment-based resource exhaustion
    Affected if System shows abnormally high memory or CPU usage with no obvious legitimate cause, potentially indicating the DoS condition

You are affected only if your system is running OpenBSD version 2.4 with IP networking enabled, as this specific version contains the vulnerable IP fragment assembly code.

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

Since OpenBSD 2.4 is extremely outdated (released 1998), the primary remediation is to upgrade to a supported OpenBSD version. Alternatively, implement edge filtering to block or rate-limit fragmented packets at network perimeter devices.

Fix this in OpenBSD Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing4.0 h
  • Review / QA2.0 h
18.0 hours of engineering $3,200
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2000-0310 — 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-2000-0310 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