Executive brief
PocketMine-MP is a server software for the Minecraft Bedrock Edition game. The software fails to validate that resource pack requests do not contain duplicate entries, allowing an authenticated attacker to send the same pack UUID multiple times in a single request. This causes the server to send the same pack repeatedly, rapidly exhausting server memory and crashing the service.
Technical details
The vulnerability exists in the STATUS_SEND_PACKS handling of ResourcePackClientResponsePacket, where the packIds array is processed without verifying uniqueness. An authenticated client can craft a malicious packet containing many duplicate valid pack UUIDs, causing the server to transmit the same resource pack multiple times and consume memory with each duplicate. The root cause is insufficient input validation—the code assumes clients will behave according to the Bedrock protocol specification, but a custom client can violate this assumption. An authenticated attacker can exploit this remotely by joining the server and sending a crafted packet; no privilege escalation or user interaction is required beyond server access. The fix, included in version 5.32.1, removes duplicates from the incoming array and disconnects clients that send excessive duplicates.
Affected products
- PocketMine PocketMine-MP before 5.32.1
Timeline
- 2025-08-30: disclosed: GitHub Security Advisory published
- 2025-09-09: advisory: CVE-2025-71417 published on NVD
- 2025-09-09: patched: Fix released in version 5.32.1