CVE-2026-86202: PocketMine-MP network amplification in ActorEventPacket

CVE-2026-86202 · Severity: medium · CVSS 4.3 · Published 2026-09-09

PocketMine-MP is a popular Minecraft server software used to host multiplayer game servers. An attacker connected to a server can send specially crafted network packets to force other players' clients to repeatedly perform animations (such as eating or drinking), consuming their bandwidth, CPU, and memory. By amplifying a small number of malicious packets into many animation events sent to all visible players, this can disrupt server performance and degrade the experience for legitimate players.

Technologies: pocketmine/pocketmine-mp (Packagist). Vendors: Packagist.

Quick answers

Is CVE-2026-86202 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-86202 being exploited in the wild.
How severe is CVE-2026-86202?
Medium severity, with a CVSS score of 4.3, published 9 September 2026.
Which products and versions are affected?
pocketmine/pocketmine-mp (Packagist) ECOSYSTEM:introduced=0,fixed=5.39.2.
Is there a fix for CVE-2026-86202?
Yes. pocketmine/pocketmine-mp (Packagist): upgrade to 5.39.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-86202 attacked?
It is attacked over the network, in a hosted service.
Am I affected by CVE-2026-86202?
Check whether you run pocketmine/pocketmine-mp (Packagist) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • pocketmine/pocketmine-mp (Packagist): upgrade to 5.39.2 or later
    composer require pocketmine/pocketmine-mp:^5.39.2

Technical details

The vulnerability is a network amplification flaw (CWE-406) in how PocketMine-MP handles ActorEventPacket messages received from clients. The server processes these packets without sufficient validation and broadcasts animation events to all nearby players, allowing an authenticated client to send a single malicious packet that triggers multiple outbound animation packets to other clients. Attack requires network access to a PocketMine-MP server and low-privilege player authentication; no user interaction is needed. An attacker can waste server resources (CPU, memory, bandwidth) and potentially disrupt game experience. The vulnerability was patched in version 5.39.2 by changing animation handling to be fully server-controlled and discarding client-originated ActorEventPacket messages.

Affected products

  • PocketMine PocketMine-MP before 5.39.2

Identifiers

  • CVE-2026-86202
  • GHSA-7hmv-4j2j-pp6f

Timeline

  • 2026-04-04: disclosed: GHSA-7hmv-4j2j-pp6f published
  • 2026-05-09: patched: Version 5.39.2 released with fix
  • 2026-09-09: other: CVE-2026-86202 assigned

References

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