Improper input validation in PocketMine-MP - #VU125431
Published: April 8, 2026
Vulnerability identifier: #VU125431
CSH Severity: Low
CVSS v4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to cause a denial of service.
The vulnerability exists due to improper input validation in ModalFormResponsePacket handling when processing oversized JSON form responses. A remote user can send a specially crafted packet containing a massive JSON array or object to cause a denial of service.
Exploitation requires the player to have a full in-game session before form responses are handled.
Affected software
PocketMine-MP
Remediation
Install security update from vendor's website.
PocketMine-MP - update to 5.39.2