CVE-2003-1433: Epic Games Unreal Engine

Medium severity, CVSS 4.3. EPSS: 1.2% chance of exploitation in the next 30 days.

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.

Affected products

• Epic Games Unreal Engine: version 226f only; version 433 only; version 436 only

Published 2003-12-31. Last modified 2026-06-16.