Summary
PocketMine-MP server crash with certain invalid JSON payloads in LoginPacket due to dependency vulnerability (again)
Workarounds
A plugin may handle DataPacketReceiveEvent for LoginPacket and check that none of the input arrays contain NULL where it's not expected, but this is rather cumbersome.
References
Proposed upstream patch for a behavior change: https://github.com/cweiske/jsonmapper/pull/211
Impact
An attacker could crash PocketMine-MP by sending malformed JSON in LoginPacket.
This happened due to the particular handling of NULL types in the json mapper which accepts NULL type values in typed arrays which PocketMine-MP did not expect.
Code processing arrays in the JSON data could then crash due to unexpected NULL elements.
GHSA-92JH-GWCH-JQ38 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (5.3.1, 4.23.1); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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This problem was fixed in 5.3.1 and 4.23.1 by updating JsonMapper to include the following commit: pmmp/netresearch-jsonmapper@4f90e8dab1c9df331fad7d3d89823404e882668c
An upstream patch for this issue was proposed via https://github.com/cweiske/jsonmapper/pull/211; however, as of 2024-05-15, the patch has not been accepted upstream due to debate about how to deal with the behavior. For now, a fork of JsonMapper is used by PocketMine-MP to workaround the issue.
Frequently Asked Questions
- What is GHSA-92JH-GWCH-JQ38? GHSA-92JH-GWCH-JQ38 is a high-severity security vulnerability in pocketmine/pocketmine-mp (composer), affecting versions >= 5.0.0, <= 5.3.0. It is fixed in 5.3.1, 4.23.1.
- How severe is GHSA-92JH-GWCH-JQ38? GHSA-92JH-GWCH-JQ38 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of pocketmine/pocketmine-mp are affected by GHSA-92JH-GWCH-JQ38? pocketmine/pocketmine-mp (composer) versions >= 5.0.0, <= 5.3.0 is affected.
- Is there a fix for GHSA-92JH-GWCH-JQ38? Yes. GHSA-92JH-GWCH-JQ38 is fixed in 5.3.1, 4.23.1. Upgrade to this version or later.
- Is GHSA-92JH-GWCH-JQ38 exploitable, and should I be worried? Whether GHSA-92JH-GWCH-JQ38 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether GHSA-92JH-GWCH-JQ38 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix GHSA-92JH-GWCH-JQ38?
- Upgrade
pocketmine/pocketmine-mpto 5.3.1 or later - Upgrade
pocketmine/pocketmine-mpto 4.23.1 or later
- Upgrade