ageLANServer: Unbounded JSON Array Allocation in AoE3 Cloud getFileURL Endpoint Leads to Remote Denial of Service

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

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

EPSS

• CVE-2026-107839: 0.41% estimated exploitation activity in the next 30 days; percentile 35.83 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary The AoE3 POST /game/cloud/getFileURL handler in luskaner/ageLANServer's bundled game server decodes an attacker-controlled names JSON array and immediately allocates response storage sized directly from the array's length (make(i.A, len(req.Names.Data))), with no request body size limit and no cap on the number of array elements anywhere in the request path. Because the default configuration ships with Authentication = 'disabled', any network client can obtain a session through unauthenticated platform login and then send a single crafted request that forces the server to allocate memory proportional to attacker-chosen input. Dynamic testing against an unmodified build confirmed both large memory-amplification growth from a single request and a full server process kill via the kernel OOM killer when a memory-constrained instance received a few concurrent oversized requests. This is a high-severity, pre-authentication (self-registration only) remote denial-of-service…

Published by the source

9 Oct 2026, 20:44 UTC

Last modified by the source

22 Oct 2026, 08:25 UTC

Source last checked

26 Oct 2026, 15:32 UTC

1. Revision 4 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-4jfq-pmq9-257h

2. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-4jfq-pmq9-257h

3. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GO-2026-6716

4. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-4jfq-pmq9-257h

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# Patch Next advisory brief: CVE-2026-107839

Advisory: ageLANServer: Unbounded JSON Array Allocation in AoE3 Cloud `getFileURL` Endpoint Leads to Remote Denial of Service
IDs: CVE-2026-107839, GHSA-4jfq-pmq9-257h
Record: https://patchnext.com/advisories/cve-2026-107839 (revision 4, source checked 26 Oct 2026, 15:32 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/luskaner/ageLANServer/server 1.8.2-0.20260809203301-1dd40166a593. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/luskaner/ageLANServer/server: affected < 1.8.2-0.20260809203301-1dd40166a593; fixed in 1.8.2-0.20260809203301-1dd40166a593

## Suggested inspection (read-only)
- Go github.com/luskaner/ageLANServer/server: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/luskaner/ageLANServer/server.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GO-2026-6716 (OSV record GO-2026-6716 lists affected ranges: Go github.com/luskaner/ageLANServer/server >=0 <1.8.2-0.20260809203301-1dd40166a593 (fixed))
- Verified: https://osv.dev/vulnerability/GHSA-4jfq-pmq9-257h (OSV record GHSA-4jfq-pmq9-257h lists affected ranges: Go github.com/luskaner/ageLANServer/server >=0 <1.8.2-0.20260809203301-1dd40166a593 (fixed))
- Verified: https://github.com/advisories/GHSA-4jfq-pmq9-257h (GitHub-reviewed advisory GHSA-4jfq-pmq9-257h lists affected ranges: Go github.com/luskaner/ageLANServer/server >=0 <1.8.2-0.20260809203301-1dd40166a593)

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