CVE-2026-107839 ageLANServer: Unbounded JSON Array Allocation in AoE3 Cloud `getFileURL` Endpoint Leads to Remote Denial of Service
Remote unauthenticated attackers can crash the ageLANServer by sending oversized JSON requests to the getFileURL endpoint, causing service disruption.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-107839?
CVE-2026-107839 is a high-severity denial of service vulnerability in luskaner ageLANServer, published on 9 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
ageLANServer provides a cross-platform web server and launcher for offline multiplayer in several Age of Empires and Age of Mythology games. Prior to version 1.15.2, the AoE3 POST /game/cloud/getFileURL handler in the bundled game server has no request body size limit or cap on the attacker-controlled JSON names array and allocates response storage directly from the unbounded array length. A remote unauthenticated client can use the default self-registration flow and send an oversized request that causes excessive memory allocation, crashes or hangs the server process, disconnects active players, and keeps the service unavailable until it is restarted. This issue is fixed in version 1.15.2.
Weakness: CWE-400
Which versions are affected by CVE-2026-107839?
3 open source packages ship an affected version, including github.com/luskaner/ageLANServer/server.
| Package | Affected | Fixed in |
|---|---|---|
github.com/luskaner/ageLANServer/server Go | All versions | 1.8.2-0.20260809203301-1dd40166a593 |
github.com/luskaner/ageLANServer/server Go | All versions | 1.8.2-0.20260809203301-1dd40166a593 |
github.com/luskaner/ageLANServer/server Go | All versions | 1.8.2-0.20260809203301-1dd40166a593 |
How do I fix CVE-2026-107839?
Upgrade github.com/luskaner/ageLANServer/server to 1.8.2-0.20260809203301-1dd40166a593 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-107839 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-107839 exists.
Sources
Also known as GHSA-4jfq-pmq9-257h, GO-2026-6716.