libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_GetBuffer, XML_Parse, XML_ParseBuffer, XML_ParserFree, or XML_ParserReset from within handlers in cases of a policy violation. Thus, a use-after-free can occur,
Exploitability
AV:LAC:HPR:NUI:NScope
S:UImpact
C:LI:LA:L4.9/CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:LMemory Safety