CVE-2026-33250 (GCVE-0-2026-33250)

Vulnerability from cvelistv5 – Published: 2026-03-23 23:38 – Updated: 2026-03-24 13:36
VLAI
Title
Crash when receiving specially-crafted packets
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-24 13:36 UTC
CWE
  • CWE-20 - Improper Input Validation
  • CWE-121 - Stack-based Buffer Overflow
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7664 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
longturn freeciv21 Affected: < 3.1.1
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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