PocketMine-MP vulnerabilities

PocketMine-MP versions before 5.39.2 fail to limit JSON payload size in ModalFormResponsePacket handling, allowing authenticated players to cause denial of service. Attackers can send modal form response packets with massive JSON arrays to exhaust server memory and CPU resources.

PocketMine-MP versions before 5.39.2 fail to validate entity despawn state when processing attack packets. Attackers can exploit a race condition by attacking a disconnecting player to trigger multiple death handlers, causing duplication of inventory items and experience.

PocketMine-MP versions before 5.39.2 contain a network amplification vulnerability in ActorEventPacket handling that allows clients to trigger consuming animations for all visible players. Attackers can send crafted ActorEventPacket messages to spam animation events to other clients and waste server CPU and memory resources.

PocketMine-MP before 5.41.1 contains a denial of service vulnerability in LoginPacket processing where large or complex structures in unknown clientData JWT properties cause excessive logging without sanitization. Attackers can send crafted LoginPackets with deeply nested or massive object structures to trigger out-of-memory conditions and crash the server.

PocketMine-MP versions before 5.42.1 contain a denial of service vulnerability in the LoginPacket handler that allows remote attackers to flood warning messages by injecting numerous junk properties into the clientData JWT. Attackers can craft malicious login packets with excessive unknown properties to waste server CPU time and degrade performance.

PocketMine-MP versions before 5.43.1 fail to properly validate the Certificate field during offline login authentication. Unauthenticated players can trigger an uninitialized property access error that crashes the server.

PocketMine-MP versions before 5.44.2 fail to properly validate multiple ResourcePackClientResponsePacket packets with STATUS_COMPLETED status during resource pack handling. Malicious clients can send batches of these packets to repeatedly trigger pre-spawn progression, creating duplicate Player objects and amplifying memory consumption and network traffic.

PocketMine-MP versions before 5.25.2 fail to limit the explode() function in packet parsing, allowing malicious clients to waste server resources. Attackers can send crafted packets with excessive delimiters to consume CPU and memory through sign editing, JWT parsing, and command parsing endpoints.

PocketMine-MP before 5.32.1 fails to validate uniqueness of pack UUIDs in ResourcePackClientResponsePacket STATUS_SEND_PACKS handling, allowing authenticated clients to trigger duplicate pack transmissions. Attackers can send multiple copies of valid pack UUIDs in a single packet to exhaust server memory and cause denial of service.

PocketMine-MP before 5.11.1 contains a denial of service vulnerability in LoginPacket JSON processing that allows remote attackers to crash the server by sending malformed JSON data. Attackers can exploit improper object initialization from scalar JSON types to trigger unset required properties, causing the application to crash.

PocketMine-MP before version 5.11.2 contains a denial of service vulnerability in BookEditPacket handling that crashes the server when an invalid inventory slot value is provided. Attackers can send a crafted BookEditPacket with an inventory slot greater than 35 to trigger an unhandled exception and crash the server.

PocketMine-MP before version 4.8.1 fails to validate dye color IDs in banner NBT data during deserialization. Attackers can provide invalid color values in inventory transactions or via commands to trigger undefined offset errors and crash the server.

PocketMine-MP before version 4.12.5 contains a denial-of-service vulnerability in ModalFormResponsePacket processing that allows attackers to cause server resource exhaustion by sending large JSON payloads. Attackers can send numerous oversized modal form response packets to consume CPU time and prevent the server from processing legitimate connections.

PocketMine-MP before 4.18.0-ALPHA2 fails to rate-limit mismatch type InventoryTransactionPacket requests, allowing attackers to trigger excessive inventory synchronization. Attackers can send numerous mismatch transactions to force the server to transmit large amounts of serialized inventory data, consuming significant bandwidth without authentication.

PocketMine-MP versions before 4.20.5 contain a denial of service vulnerability in LoginPacket JSON parsing due to improper validation in the JsonMapper dependency. Attackers can send malformed JSON structures in LoginPacket to crash the server.

PocketMine-MP versions >= 4.20.0 before 4.22.3 (and before 5.2.1 in the 5.x branch) fail to validate NBT tag types in BlockActorDataPacket. A player can crash the server by sending a packet containing sign NBT data with an incorrect tag type, triggering an unhandled UnexpectedTagTypeException that terminates the server process.

PocketMine-MP versions before 5.3.1 and 4.23.1 contain a denial of service vulnerability in LoginPacket JSON parsing due to improper null value handling in arrays. Attackers can send malformed JSON with unexpected null elements in LoginPacket to crash the server.

PocketMine-MP versions before 5.3.1 and 4.23.1 fail to validate that the identityPublicKey in LoginPacket uses the required secp384r1 elliptic curve. Attackers can provide LoginPackets with keys using different curves or non-EC key types to pass login verification but trigger an uncaught exception during ECDH key derivation, crashing the server.

PocketMine-MP before 3.26.5 and 4.0.x before 4.0.5 does not limit book page text length, page count, or author/title length. A player who obtains a writable book can create oversized NBT ('book bombs'), causing excess bandwidth consumption and server crashes (exceeding the 1 MB chunk size limit when saving region-based worlds in PM3, or exceeding the 32 KiB TAG_String limit in PM4).

PocketMine-MP before versions 3.26.5 and 4.0.5 fails to validate the length of skin data fields submitted by players, allowing values to exceed the 32767 byte TAG_String limit. Attackers can submit oversized fields like skinID or geometryName to trigger exceptions during NBT serialization, causing server crashes.

PocketMine-MP 3.x (before 3.27.0) does not implement Minecraft Bedrock protocol encryption, so the server cannot verify that a connecting client possesses the private key corresponding to its login token. An attacker who captures a valid login from another player's session (for example by tricking the player into connecting to an attacker-controlled server) can replay that login to impersonate the victim and pass XBOX Live authentication until the JWT token expires (typically 2-3 days). This affects servers directly reachable over the internet that are not behind a proxy with encryption enabled. Fixed in 4.0.0 and backported to 3.27.0.

PocketMine-MP before 4.0.6 does not validate facing values in PlayerActionPacket (for START_BREAK and CRACK_BREAK actions) or in UseItemTransactionData (typically within InventoryTransactionPacket). A remote authenticated attacker can send crafted packets with invalid facing values (e.g., negative or out-of-range) to crash the server, resulting in a denial of service.

PocketMine-MP before 4.0.7 contains an unhandled exception vulnerability in the ModalFormResponsePacket handler when processing malformed JSON from clients. Attackers can send specially crafted form response packets with invalid JSON to trigger an uncaught InvalidArgumentException, causing server crashes.

PocketMine-MP versions before 4.2.3 fail to validate damage metadata values in tool and armor item NBT data received from clients. Attackers can send negative or out-of-range damage values in itemstack NBT to trigger unhandled exceptions in the Durable class, causing server crashes.

PocketMine-MP versions before 4.2.9 fail to properly validate NBT data types during deserialization of inventory transaction packets from clients. Attackers can send crafted inventory transactions with malformed NBT tags to trigger server crashes and cause denial of service.

PocketMine-MP before 4.2.10 fails to validate the total length of incoming chat message blobs before splitting them by newline characters, allowing attackers to send large messages containing many newlines. Malicious clients can send megabyte-sized chat packets and bombard the server with thousands of such messages, causing server lockups lasting seconds or minutes.

PocketMine-MP before version 4.4.2 fails to properly validate item IDs received from clients in itemstack NBT data. Attackers can send crafted item IDs outside the valid range to trigger an uncaught exception that crashes the server.

PocketMine-MP before 4.7.2 fails to properly handle exceptions from the adhocore/json-comment library when parsing skin geometry data. Attackers can send login or skin packets with invalid geometry JSON to trigger an unhandled RuntimeException, causing server crash.

PocketMine-MP before 4.12.3 fails to limit unauthenticated sessions, allowing attackers to exhaust player slots by creating sessions without sending LoginPacket. Attackers can flood the server with unauthenticated connections that occupy max-player slots, preventing legitimate players from joining.

PocketMine-MP versions before 3.18.1 fail to validate NaN or INF values in MovePlayerPacket position and rotation fields. Malicious clients can send crafted movement packets with invalid floating-point values to crash servers through unhandled mathematical operations or prevent clients from rendering other players.

PocketMine-MP before 4.0.3 does not perform case-insensitive matching when removing operator entries from ops.txt. The removeOp function lowercases the supplied name but only removes an exactly matching entry, so an operator name stored with non-lowercase letters cannot be revoked using the deop command, leaving the player as an operator until the entry is removed from ops.txt manually.

PocketMine-MP versions before 3.15.4 contain a denial of service vulnerability in the InventoryTransaction component's findResultItem() method. Malicious clients can send specially crafted InventoryTransactionPackets with multiple conflicting pathways to cause exponential processing complexity, freezing the server.

PocketMine-MP versions prior to 4.18.1 have an improper input validation vulnerability in inventory transaction handling. A remote attacker with a valid player session can request dropping more items than available in the hotbar, causing a server crash and denial of service.