CVE-2023-54393

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.

CVSS 4.0

8.7CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

CVSS 3.1

7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

0.6% chance of exploitation in the next 30 days; higher than 49% of CVEs (scores of 2026-10-25)

CWE

CWE-20

Published

2026-09-09

Modified

2026-10-08

Record from

the NVD, synced 2026-10-19

References

• https://github.com/pmmp/PocketMine-MP/commit/09668a37d66c6023685a948b7550c918620e98f2
• https://github.com/pmmp/PocketMine-MP/commit/a31902a31f5b6fdb832f57c0e3a3f16a3b41c012
• https://github.com/pmmp/PocketMine-MP/security/advisories/GHSA-pqp3-8rrw-g8vm
• https://www.vulncheck.com/advisories/pocketmine-mp-before-4.20.5-denial-of-service-via-loginpacket

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