PocketMine-MP has potential memory/network vulnerability from repeated ResourcePackClientResponsePacket packets

Exploitation

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

CVSS 4.0

2.3 · CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N · score source

EPSS

• CVE-2026-86198: 0.38% estimated exploitation activity in the next 30 days; percentile 32.26 (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 During the resource pack stage of logging in, after the server sends `ResourcePackStackPacket`, a malicious client can send a batch of multiple `ResourcePackClientResponsePacket` packets with status `ResourcePackClientResponsePacket::STATUS_COMPLETED` causing the server to repeatedly execute pre-spawn progression.

Impact Multiple `Player` objects can be created for just a single session, increasing memory usage and amplifying outbound network traffic from duplication of large pre-spawn packets such as `AvailableCommandsPacket` and `CreativeContentPacket`.

Workarounds Plugins can use their own `PacketHandler` classes that reject/ignore any extra `ResourcePackClientResponsePacket` packets.

Patches This issue was patched in https://github.com/pmmp/PocketMine-MP/commit/7a27894146a04964ab628ed9033140fdbf887ff3 and released in 5.44.2.

Published by the source

29 Oct 2026, 16:32 UTC

Last modified by the source

29 Oct 2026, 16:45 UTC

Source last checked

30 Oct 2026, 07:05 UTC

1. Revision 2 · amended · 30 Oct 2026

   Amended from osv record GHSA-pg53-p7qp-65cv

2. Revision 1 · created · 29 Oct 2026

   Published from ghsa record GHSA-pg53-p7qp-65cv

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# Patch Next advisory brief: CVE-2026-86198

Advisory: PocketMine-MP has potential memory/network vulnerability from repeated ResourcePackClientResponsePacket packets
IDs: CVE-2026-86198, GHSA-pg53-p7qp-65cv
Record: https://patchnext.com/advisories/ghsa-pg53-p7qp-65cv (revision 2, source checked 30 Oct 2026, 07:05 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Low (CVSS 2.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: pocketmine/pocketmine-mp 5.44.2. A vendor fix does not mean a deployment is fixed.

## Affected components
- Packagist pocketmine/pocketmine-mp: affected < 5.44.2; fixed in 5.44.2

## Suggested inspection (read-only)
- Packagist pocketmine/pocketmine-mp: 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 pocketmine/pocketmine-mp.
- 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://github.com/advisories/GHSA-pg53-p7qp-65cv (GitHub-reviewed advisory GHSA-pg53-p7qp-65cv lists affected ranges: Packagist pocketmine/pocketmine-mp >=0 <5.44.2)
- Verified: https://osv.dev/vulnerability/GHSA-pg53-p7qp-65cv (OSV record GHSA-pg53-p7qp-65cv lists affected ranges: Packagist pocketmine/pocketmine-mp >=0 <5.44.2 (fixed))

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