source_field,target_field,rule,notes
AV,AV,"Network->N, Adjacent->A, Local->L, Physical->P","Preserve mapping; CVSS 4 AT handled separately"
AC,AC,"Low->L, High->H",""
PR,PR,"None->N, Low->L, High->H",""
UI,UI,"None->N, Passive->P, Active->A","CVSS3 has R (Required) approximate with A"
VC,C,"High->H, Low->L, None->N","Impact mapping: VC→Confidentiality"
VI,I,"High->H, Low->L, None->N",""
VA,A,"High->H, Low->L, None->N",""
SC,S,"High->C, Low->C, None->U","Scoped impact collapses to Scope Changed/Unchanged; default Changed when SC>None"
SI,S,"High->C, Low->C, None->U","Same as SC"
SA,S,"High->C, Low->C, None->U","Same as SC"
AT,N/A,"drop","Attack requirements not represented in CVSS3"
Threat,Temporal,"map to E: NotDefined","Threat metrics not supported; set Temporal NotDefined"
Environmental,Environmental,"map CR/IR/AR to CR/IR/AR; map MV* to unchanged"