HistoryStore::put_historic_txns uses an assert! to enforce invariants about HistoricTransaction.block_number (must be within the macro block being pushed and within the same epoch). During history sync, a peer can influence the history: &[HistoricTransaction] input passed into Blockchain::push_history_sync, and a malformed history list can violate these invariants and trigger a panic.
extend_history_sync calls this.history_store.add_to_history(..) before comparing the computed history root against the macro block header (block.history_root()), so the panic can happen before later rejection checks run.
The patch for this vulnerability is included as part of v1.3.0.
No known workarounds.
Exploitability
AV:NAC:HPR:NUI:RScope
S:UImpact
C:NI:NA:H5.3/CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H