CVE-2026-33250

Publication date 24 March 2026

Last updated 14 September 2026

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

7.5 · High

Score breakdown

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.

Status

Package Ubuntu Release Status
freeciv 26.04 LTS resolute
Not affected
25.10 questing Ignored end of life, was needs-triage
24.04 LTS noble
Fixed 3.1.0+ds-1ubuntu0.1~esm1
22.04 LTS jammy
Fixed 2.6.6-1ubuntu0.1~esm1
20.04 LTS focal
Fixed 2.6.2-1ubuntu0.1~esm1
18.04 LTS bionic
Fixed 2.5.10-1ubuntu0.1~esm1
16.04 LTS xenial
Fixed 2.5.3-1ubuntu0.1~esm1

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Severity score breakdown

CVSS version: CVSS v3.0

Base score 7.5 · High

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

    • USN-8754-1
    • Freeciv vulnerability
    • 14 September 2026

Other references

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