In libxml2 before 2.15.4, there is a heap-based buffer overflow in xmlXPtrEvalXPtrPart because of xmlXPtrEval xpointer length saturation.
2.15.4Exploitability
AV:LAC:HPR:NUI:NScope
S:UImpact
C:HI:HA:L6.9/CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:LOther