{"id":"CVE-2023-54393","aliases":["GHSA-pqp3-8rrw-g8vm"],"url":"https://o3.security/vulnerability/CVE-2023-54393","summary":"PocketMine-MP before 4.20.5 Denial of Service via LoginPacket","details":"### Impact\nAn attacker could crash PocketMine-MP by sending malformed JSON in `LoginPacket`.\n\nThis 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.\n\n### Patches\nThe 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.\n\n### Workarounds\n- Users of PocketMine-MP source installations may manually install the patched version of JsonMapper by backporting commit pmmp/PocketMine-MP@09668a37d66c6023685a948b7550c918620e98f2.\n- 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.\n\n### References\ncweiske/jsonmapper#210\n","published":"2026-09-09T13:31:52.111Z","modified":"2026-10-21T02:50:23.043964507Z","cvss":null,"epss":{"score":0.0035,"percentile":0.28318,"asOf":"2026-09-12"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Packagist","name":"pocketmine/pocketmine-mp","fixedVersion":"4.20.5"},{"ecosystem":"Packagist","name":"pocketmine/pocketmine-mp","fixedVersion":"4.21.1"}],"fix":{"url":"https://github.com/pmmp/PocketMine-MP/commit/09668a37d66c6023685a948b7550c918620e98f2","label":"pmmp/PocketMine-MP@09668a3"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/54xxx/CVE-2023-54393.json"},{"type":"ADVISORY","url":"https://github.com/pmmp/PocketMine-MP/security/advisories/GHSA-pqp3-8rrw-g8vm"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-54393"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/pocketmine-mp-before-4.20.5-denial-of-service-via-loginpacket"},{"type":"FIX","url":"https://github.com/pmmp/PocketMine-MP/commit/09668a37d66c6023685a948b7550c918620e98f2"},{"type":"FIX","url":"https://github.com/pmmp/PocketMine-MP/commit/a31902a31f5b6fdb832f57c0e3a3f16a3b41c012"},{"type":"WEB","url":"https://github.com/cweiske/jsonmapper/pull/210"},{"type":"WEB","url":"https://github.com/pmmp/netresearch-jsonmapper/commit/a31902a31f5b6fdb832f57c0e3a3f16a3b41c012"},{"type":"PACKAGE","url":"https://github.com/pmmp/PocketMine-MP"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-21T02:50:23.043964507Z"}}