A remote code execution (RCE) vulnerability exists in fastjson 1.2.68 through 1.2.83. This vulnerability is exploitable under fastjson's stock default configuration — no AutoType enablement required, no classpath gadget required.
Exploitability
AV:NAC:HPR:NUI:NScope
S:CImpact
C:HI:HA:H9/CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:HInput Validation
Serialization