yyjson through 0.8.0 has a double free, leading to remote code execution in some cases, because the pool_free function lacks loop checks. (pool_free is part of the pool series allocator, along with pool_malloc and pool_realloc.)
Exploitability
AV:NAC:LPR:NUI:NScope
S:UImpact
C:LI:HA:L8.6/CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L