CVE-2023-54393
highpriority · track · 30EPSS 0.006 · 50 %ileUSEPSS · scored 2026-10-27
PocketMine-MP versions before 4.20.5 contain a denial of service vulnerability in LoginPacket JSON parsing due to improper validation in the JsonMapper dependency. Attackers can send malformed JSON structures in LoginPacket to crash the server.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.6–8.7
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (2)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- GHSA-pqp3-8rrw-g8vmPocketMine-MP vulnerable to server crash with certain invalid JSON payloads in `LoginPacket` due to vulnerable dependency2023-06-06ghsa · osvUS
### Impact An attacker could crash PocketMine-MP by sending malformed JSON in `LoginPacket`. This happened due to a bug in [`netresearch/jsonmapper`](https://github.com/cweiske/JsonMapper). The library wasn't doing proper checks when mapping JSON arrays and objects onto scalar model properties such as strings. ### Patches The problem was fixed in a fork of JsonMapper in dktapps/JsonMapper@a31902a31f5b6fdb832f57c0e3a3f16a3b41c012. PocketMine-MP releases 4.20.5 and 4.21.1 have been released with the fix. ### Workarounds - Users of PocketMine-MP source installations may manually install the patched version of JsonMapper by backporting commit pmmp/PocketMine-MP@09668a37d66c6023685a948b7550c918620e98f2. - A plugin may also be able to workaround this issue by using `DataPacketReceiveEvent` to attempt detection of suspicious payloads. An `ErrorException` will be thrown in the crash case, which can be caught by plugins. ### References cweiske/jsonmapper#210
sources
Which sources assert this record, and when.
references (4) nvd
External citations — patches, advisories, analysis.
- https://github.com/pmmp/PocketMine-MP/commit/09668a37d66c6023685a948b7550c918620e98f2
- https://github.com/pmmp/PocketMine-MP/commit/a31902a31f5b6fdb832f57c0e3a3f16a3b41c012
- https://github.com/pmmp/PocketMine-MP/security/advisories/GHSA-pqp3-8rrw-g8vm
- https://www.vulncheck.com/advisories/pocketmine-mp-before-4.20.5-denial-of-service-via-loginpacket
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