CVE-2026-33250

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/longturn/freeciv21/commit/ad8e18ca22595529599782b2984bf44df8d69ed6
https://github.com/longturn/freeciv21/releases/tag/v3.1.1
https://github.com/longturn/freeciv21/security/advisories/GHSA-f76g-6w3f-f6r3
https://redmine.freeciv.org/issues/1955

Configurations

No configuration.

History

No history.

Information

Published : 2026-03-24 00:16

Updated : 2026-03-24 15:53

NVD link : CVE-2026-33250

Mitre link : CVE-2026-33250

CVE.ORG link : CVE-2026-33250

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

CWE-121

Stack-based Buffer Overflow

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