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().

CVSS

No CVSS.

References

Link	Resource
https://github.com/python/cpython/commit/063d4555c94ef412c731527dbf30193327f2ee82
https://github.com/python/cpython/commit/476fb09cdb0d73e645849d98c610e7e5697ce7c9
https://github.com/python/cpython/commit/89f29c760c02774b099ddd6863268eb13fa3946a
https://github.com/python/cpython/commit/b09a67a20c464f8288c9f9a6b9c7082a74560024
https://github.com/python/cpython/commit/b30c7fa9edd921a118f286e9f90f560777fa693b
https://github.com/python/cpython/commit/fd78b565d7c326f96ae903ab945b47f35d829cf4
https://github.com/python/cpython/issues/98820
https://github.com/python/cpython/pull/153694
https://mail.python.org/archives/list/security-announce@python.org/thread/KQ7NBMCPAZJHRROQXJQE4GMXGLD5KHBS/

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-10 14:17

Updated : 2026-08-18 15:04

NVD link : CVE-2026-18503

Mitre link : CVE-2026-18503

CVE.ORG link : CVE-2026-18503

JSON object : View

Products Affected

No product.

CWE

CWE-1176

Inefficient CPU Computation

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