CVE-2026-18503

Attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing and consume significant CPU when applications pass unbounded input to csv.Sniffer.sniff...

CVE-2026-18503

CVE-2026-18503 affects Python’s csv.Sniffer.sniff() when fed attacker-controlled, unbounded CSV input. The dialect sniffing process can trigger super-linear regular-expression work, leading to significant CPU consumption. The issue is triggered during normal operation of csv.Sniffer.sniff() with ...