What is CVE-2023-54393?

CVE-2023-54393 is a high-severity vulnerability in Pmmp Pocketmine-Mp, classified under Improper Input Validation. CVSS score: 7.5/10. Published 2026-09-09.

How severe is CVE-2023-54393?

High severity. CVSS v3 base score is 7.5 out of 10.

Improper input validation in Pmmp Pocketmine-Mp

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.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

Published 2026-09-09 · last modified 2026-10-08.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.004 (27.5th percentile), scored 2026-10-25.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 28th percentile — 27.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Pmmp Pocketmine-Mp

Weakness classification (CWE)

CWE-20 — Improper Input Validation

References

github.com/pmmp/PocketMine-MP/security/advisories/GHSA-pqp3-8rrw-g8vm (vendor-advisory)
github.com/pmmp/PocketMine-MP/commit/a31902a31f5b6fdb832f57c0e3a3f16a3b41c012 (patch)
github.com/pmmp/PocketMine-MP/commit/09668a37d66c6023685a948b7550c918620e98f2 (patch)
www.vulncheck.com/advisories/pocketmine-mp-before-4.20.5-denial-of-service-via-… (third-party-advisory)

Frequently asked questions

What is CVE-2023-54393?: CVE-2023-54393 is a high-severity vulnerability in Pmmp Pocketmine-Mp, classified under Improper Input Validation. CVSS score: 7.5/10. Published 2026-09-09.
How severe is CVE-2023-54393?: High severity. CVSS v3 base score is 7.5 out of 10.