Half LifeApplication · Valve Software

CVE-2004-0724

MEDIUM · 5.0 CVSS v2.0 Published 2004-07-27
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
The Half-Life engine before July 7 2004 allows remote attackers to cause a denial of service (server or client crash) via an empty fragmented packet.

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 · moderate confidence

The Half-Life engine before July 7 2004 contains a vulnerability where remote attackers can send empty fragmented packets to cause a denial of service, crashing either the game server or connected clients. The vulnerability is in the packet handling logic for fragmented packets.

MitigationUpdate the Half-Life engine to a version released after July 7 2004, which contains the patch for this vulnerability. If using legacy/modified engine branches, ensure packet validation is implemented to reject empty fragmented packets.

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
Half LifeApplication
Affected:= 1.1.0.4= 1.1.0.8= 1.1.0.9= 1.1.1.0
Half Life Dedicated ServerApplication
Affected:= 3.1= 3.1.0.4= 3.1.0.5= 3.1.0.6= 3.1.0.7= 3.1.0.8= 3.1.0.9= 3.1.1.0= 3.1.1.1c1= 3.1.1.1d= 3.1.1.1e= 3.1.3

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 Half-Life engine version
    Launch the Half-Life client or dedicated server binary with the -version or -v parameter, or check the version displayed in the console at startup. For dedicated servers, check the hlds_run or srcds console output.
    Affected if The displayed version matches any of: 1.1.0.4, 1.1.0.8, 1.1.0.9, 1.1.1.0 for client, or 3.1, 3.1.0.4, 3.1.0.5, 3.1.0.6, 3.1.0.7, 3.1.0.8, 3.1.0.9, 3.1.1.0, 3.1.1.1c1, 3.1.1.1d, 3.1.1.1e, 3.1.3 for dedicated server.
  2. Check engine binary file version
    Locate the main executable (hl.exe for client, hlds.exe for dedicated server) and view its file properties to see the Product Version field.
    Affected if The file properties show a version matching any of the affected versions listed above.
  3. Determine if running as server or client
    Confirm whether the installation is a client instance or a dedicated server by checking if hlds.exe, srcds.exe, or hlds_run is the running process.
    Affected if Both client and server installations are affected; no distinction needed for detection.
  4. Check build date of engine files
    View the creation or modification date of the core engine files such as hw.dll, sw.dll, or the main server executable.
    Affected if The engine files were created or last updated before July 7 2004, indicating an unpatched version.

You are affected if your Half-Life engine version matches any of the listed affected versions or if your engine files predate the July 7 2004 patch date.

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

Update the Half-Life engine to a version released after July 7 2004, which contains the patch for this vulnerability. If using legacy/modified engine branches, ensure packet validation is implemented to reject empty fragmented packets.

Fix this in Half Life Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing1.0 h
  • Review / QA1.0 h
5.0 hours of engineering $890
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2004-0724 — 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-2004-0724 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
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  • Version or environment caveats, and links to real fixes
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