Vulnerability · Published Sep 9, 2026 · Assigned by VulnCheck

CVE-2026-86204PocketMine-MP before 5.39.2 Denial of Service via ModalFormResponsePacket

Medium 6.5

In plain English

A medium-severity uncontrolled resource consumption in PocketMine-MP from pmmp. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 38% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)6.5Medium

Exploit odds (30 days)0.4%top 62.0% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

PocketMine-MP versions before 5.39.2 fail to limit JSON payload size in ModalFormResponsePacket handling, allowing authenticated players to cause denial of service. Attackers can send modal form response packets with massive JSON arrays to exhaust server memory and CPU resources, rendering the server unresponsive.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Packagist	pocketmine/pocketmine-mp	5.39.2	GHSA-788v-5pfp-93ff

Affected products (as reported)

Vendor	Product	Versions
pmmp	PocketMine-MP	0 – before 5.39.2

Weakness: CWE-400 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

References

GitHub Security Advisory (GHSA-788v-5pfp-93ff) vendor-advisory
VulnCheck Advisory: PocketMine-MP before 5.39.2 Denial of Service via ModalFormResponsePacket third-party-advisory