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CVE-2003-1433· NVD / CVE Program· CNA mitre

Epic Games Unreal Engine 226f through 436 does not validate the challenge key, which allows remote attackers to exhaust the player limit by

Epic Games Unreal Engine 226f through 436 does not validate the challenge key, which allows remote attackers to exhaust the player limit by joining the game multiple times.

MediumCVSS 4.3 · v2.0—No exploit No fix recorded
Published
Dec 31, 2003
Updated
Jun 16, 2026
EPSS
1.2% · 66th percentile
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Action score

17

Monitor

Low priority for now.

CVSS
17 / 40 · 4.3 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 1.2%

Affected systems

VendorProduct
epic gamesunreal engine

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • epic games unreal engine226f
  • epic games unreal engine433
  • epic games unreal engine436

Same product

epic games: all records

Other highest-scoring records for the same primary product.

  • CVE-2003-1432Epic Games Unreal Engine 226f through 436 allows remote attackers to cause a denial of service (CPU consumption or crash) and possibly execu
    42Plan
  • CVE-2003-1431Buffer overflow in Epic Games Unreal Engine 226f through 436 allows remote attackers to cause a denial of service (crash) via a long host st
    30Monitor
  • CVE-2004-1805Format string vulnerability in games using the Epic Games Unreal Engine 436 allows remote attackers to cause a denial of service (crash) and
    22Monitor
  • CVE-2007-4442Stack-based buffer overflow in the logging function in the Unreal engine, possibly 2003 and 2004, as used in the internal web server, allows
    21Monitor
  • CVE-2007-4443The UCC dedicated server for the Unreal engine, possibly 2003 and 2004, on Windows allows remote attackers to cause a denial of service (con
    21Monitor
  • CVE-2004-1958Directory traversal vulnerability in manifest.ini in Unreal engine allows remote attackers to overwrite arbitrary files via ..
    21Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

The product’s vendor appears in a public program. Matched by name; verify the scope text in the program.

Technical details

Attack conditions

    If successful

    Confidentiality
    none
    Integrity
    none
    Availability
    P · the service can be disrupted
    Attack complexity
    M
    Confidentiality impact
    None
    Integrity impact
    None
    Availability impact
    P

    Weakness class (CWE)

    CWE-287 · Improper Authentication

    CVSS vector

    AV:N/AC:M/Au:N/C:N/I:N/A:P

    nvd-primary

    Root cause

    Authentication is added route by route instead of being enforced in one place. When a route added later bypasses the shared middleware, the session check never runs for it.

    The bug in code

    The whole CWE-287 class

    A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

    Vulnerable

    ts
    app.use("/admin", requireSession, adminRouter);
// Route added later skips the middlewareapp.post("/admin-api/config", updateConfig);

    Fixed

    ts
    const admin = express.Router();admin.use(requireSession, requireRole("admin"));
admin.post("/config", updateConfig);app.use("/admin", admin);

    Attack context

    MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

    Noroxi analysis

    No Noroxi analysis for this record yet

    We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.

    We use this product, ask for help

    Change log

    No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.

    References

    Vendor advisories and official records. Exploit/PoC links are deliberately left out.

    All records