dbcve.org
FreeBSDOperating system

CVE-2002-0830

MEDIUM · 5.0 CVSS v2.0 Published 2002-08-12
Fix available
A fix is available. Upgrade to after 4.6.1 or later.
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
Network File System (NFS) in FreeBSD 4.6.1 RELEASE-p7 and earlier, NetBSD 1.5.3 and earlier, and possibly other operating systems, allows remote attackers to cause a denial of service (hang) via an RPC message with a zero length payload, which causes NFS to reference a previous payload and enter an infinite loop.

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

NFS implementations in FreeBSD 4.6.1 RELEASE-p7 and earlier and NetBSD 1.5.3 and earlier contain a vulnerability where an RPC message with a zero-length payload causes the NFS server to reference a previous payload incorrectly, resulting in an infinite loop and system hang.

MitigationApply vendor patches or upgrade to a supported version of FreeBSD or NetBSD. For systems that cannot be immediately patched, restrict NFS access to trusted networks or disable NFS until patching is feasible.

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
FreeBSDOperating system
Affected:<= 4.6.1

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
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. Identify the operating system
    Run 'uname -a' to determine if the system is FreeBSD or NetBSD
    Affected if The system is not FreeBSD or NetBSD (this CVE only affects these systems)
  2. Check the FreeBSD version
    Run 'uname -r' or 'cat /etc/motd' to obtain the exact FreeBSD version number
    Affected if The version is 4.6.1 RELEASE-p7 or earlier (any 4.x version up to and including 4.6.1)
  3. Verify NFS server is enabled
    Check /etc/rc.conf for 'nfs_server_enable="YES"' or inspect /etc/exports for exported filesystems
    Affected if NFS server is enabled and exports exist - the vulnerability only triggers when the NFS daemon (nfsd) is running
  4. Confirm the NFS daemon is running
    Run 'ps aux | grep nfsd' or check for nfsd processes using 'sockstat -P tcp -p 2049' to see if the NFS server is listening on port 2049
    Affected if The nfsd process is actively running and listening for NFS connections

You are affected if you are running FreeBSD version 4.6.1 or earlier with the NFS server daemon (nfsd) enabled and running.

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
Upgrade available Upgrade to a release after 4.6.1
Interim mitigation

Apply vendor patches or upgrade to a supported version of FreeBSD or NetBSD. For systems that cannot be immediately patched, restrict NFS access to trusted networks or disable NFS until patching is feasible.

Fix this in FreeBSD Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing4.0 h
  • Review / QA2.0 h
10.0 hours of engineering $1,720
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,752.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2002-0830 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2002-0830 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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