Description
Freeciv21 is a free open source, turn-based, empire-building strategy game. Versions prior to 3.1.1 crash with a stack overflow when receiving specially-crafted packets. A remote attacker can use this to take down any public server. A malicious server can use this to crash the game on the player's machine. Authentication is not needed and, by default, logs do not contain any useful information. All users should upgrade to Freeciv21 version 3.1.1. Running the server behind a firewall can help mitigate the issue for non-public servers. For local games, Freeciv21 restricts connections to the current user and is therefore not affected.
Problem types
CWE-20: Improper Input Validation
CWE-121: Stack-based Buffer Overflow
Product status
References
github.com/...eciv21/security/advisories/GHSA-f76g-6w3f-f6r3
github.com/...ommit/ad8e18ca22595529599782b2984bf44df8d69ed6
github.com/longturn/freeciv21/releases/tag/v3.1.1
redmine.freeciv.org/issues/1955