---
id: CVE-2023-54393
title: >-
  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
summary: >-
  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 …
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-20
vendor: pmmp
product: PocketMine-MP
affected:
  - PocketMine-MP
published: '2026-09-09'
updated: '2026-09-14'
sourceUpdated: '2026-09-14T14:17:06.883'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2023-54393'
references:
  - url: >-
      https://github.com/pmmp/PocketMine-MP/commit/09668a37d66c6023685a948b7550c918620e98f2
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/pmmp/PocketMine-MP/commit/a31902a31f5b6fdb832f57c0e3a3f16a3b41c012
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/pmmp/PocketMine-MP/security/advisories/GHSA-pqp3-8rrw-g8vm
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/pocketmine-mp-before-4.20.5-denial-of-service-via-loginpacket
    label: disclosure@vulncheck.com
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-14T13:15:03.387351Z'
epss: 0.0035
epssPercentile: 0.25995
ingestedAt: '2026-09-14T15:23:07.418Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.