CVE-2026-18503
Attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing and consume significant CPU when
CVSS
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No CVSS
EPSS
0.1%
p2
KEV
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Exploit Today
1
0-100
Published: Aug 10, 2026 · Last modified: Oct 23, 2026 · CWE-1176
0.1%EPSS · 30 days0.1%
2026-09-262026-10-23
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().
- github.comhttps://github.com/python/cpython/commit/063d4555c94ef412c731527dbf30193327f2ee82
- github.comhttps://github.com/python/cpython/commit/476fb09cdb0d73e645849d98c610e7e5697ce7c9
- github.comhttps://github.com/python/cpython/commit/89f29c760c02774b099ddd6863268eb13fa3946a
- github.comhttps://github.com/python/cpython/commit/b09a67a20c464f8288c9f9a6b9c7082a74560024
- github.comhttps://github.com/python/cpython/commit/b30c7fa9edd921a118f286e9f90f560777fa693b
- github.comhttps://github.com/python/cpython/commit/fd78b565d7c326f96ae903ab945b47f35d829cf4
- github.comhttps://github.com/python/cpython/issues/98820
- github.comhttps://github.com/python/cpython/pull/153694
- mail.python.orghttps://mail.python.org/archives/list/security-announce@python.org/thread/KQ7NBMCPAZJHRROQXJQE4GMXGLD5KHBS/
No related CVEs by CWE or product.