GHSA-92jh-gwch-jq38
HIGHPocketMine-MP server crash with certain invalid JSON payloads in `LoginPacket` due to dependency vulnerability (again)
Blast Radius
pocketmine/pocketmine-mp🐘pocketmine/pocketmine-mpReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
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.
Patches
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.
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
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | pocketmine/pocketmine-mp | ≥ 5.0.0&&< 5.3.1 | 5.3.1 |
| 🐘Packagist | pocketmine/pocketmine-mp | all versions | 4.23.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pocketmine/pocketmine-mp. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update pocketmine/pocketmine-mp to 5.3.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-92jh-gwch-jq38 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-92jh-gwch-jq38 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-92jh-gwch-jq38. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-92jh-gwch-jq38 in your dependencies?
O3 detects GHSA-92jh-gwch-jq38 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.