Vulnerability · Published Sep 12, 2026 · Assigned by VulnCheck

CVE-2026-90557Freeciv 3.1.0 through 3.2.5 Out-of-Bounds Read via Savegame

Medium 6.1

In plain English

A medium-severity out-of-bounds read in freeciv from freeciv. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 8% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)6.1Medium

Exploit odds (30 days)0.2%top 92.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Freeciv versions 3.1.0 through 3.2.5 contain an out-of-bounds read vulnerability in sg_load_player_unit() when processing savegame files with invalid unit activity indices. An attacker can craft a malicious savegame file with an out-of-range activity index that bypasses bounds checking and causes a crash or limited heap memory exposure when loaded.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:12	freeciv	no fix listed	DEBIAN-CVE-2026-90557
Debian:13	freeciv	no fix listed	DEBIAN-CVE-2026-90557
Debian:14	freeciv	3.2.6+ds-1	DEBIAN-CVE-2026-90557
Ubuntu:26.04:LTS	freeciv	no fix listed	UBUNTU-CVE-2026-90557

Affected products (as reported)

Vendor	Product	Versions
freeciv	freeciv	3.1.0 – before 3.2.6

Weakness: CWE-125 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H

References

Patch Commit patch
https://github.com/freeciv/freeciv product
https://redmine.freeciv.org/issues/2162 issue-tracking
https://github.com/freeciv/freeciv/blob/R3_2_5/server/savegame/savegame3.c#L6108 technical-description
freeciv R3_2_6 Release Notes release-notes
https://github.com/freeciv/freeciv/blob/R3_2_5/server/savegame/savegame2.c#L4282 technical-description
VulnCheck Advisory: Freeciv 3.1.0 through 3.2.5 Out-of-Bounds Read via Savegame third-party-advisory