CVE-2026-86200

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.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/pmmp/PocketMine-MP/commit/c1d4a813fb8c21bfd8b9affd040da864b794df71
https://github.com/pmmp/PocketMine-MP/security/advisories/GHSA-xp4f-g2cm-rhg7
https://www.vulncheck.com/advisories/pocketmine-mp-before-5.42.1-logdos-via-loginpacket-clientdata-jwt

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-09 14:17

Updated : 2026-09-09 20:20

NVD link : CVE-2026-86200

Mitre link : CVE-2026-86200

CVE.ORG link : CVE-2026-86200

JSON object : View

Products Affected

No product.

CWE

CWE-779

Logging of Excessive Data

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