CVE Catalog

CVE-2026-18503

LowCVSS 2.4
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.12%

2th percentile - higher than 2% of all known CVEs

Summary

A vulnerability in Python's csv.Sniffer where attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing, consuming significant CPU.

Risk Assessment

An attacker can cause server or application overload, leading to denial of service (DoS).

Recommendation

Limit the size of input data passed to csv.Sniffer.sniff() or apply timeouts.

Original NVD description (English source)

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().

Vulnerability data from NVD (NIST) · CISA KEV · EPSS