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{"bugzilla": {"description": "python: Python: Denial of Service via super-linear regular expression work in csv.Sniffer.sniff()", "id": "2513510", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2513510"}, "csaw": false, "cvss3": {"cvss3_base_score": "2.8", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:L", "status": "draft"}, "cwe": "CWE-1333", "details": ["Attacker-controlled CSV samples can trigger super-linear \nregular-expression work during dialect sniffing and consume significant \nCPU when applications pass unbounded input to csv.Sniffer.sniff().", "A flaw was found in the `csv.Sniffer.sniff()` function within Python. An attacker can exploit this by providing specially crafted CSV samples, which can trigger super-linear regular-expression processing during dialect sniffing. This excessive processing consumes significant CPU resources, potentially leading to a Denial of Service (DoS) for applications that process unbounded input using this function."], "name": "CVE-2026-18503", "public_date": "2026-08-10T13:45:31Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-18503\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-18503\nhttps://github.com/python/cpython/issues/98820\nhttps://github.com/python/cpython/pull/153694\nhttps://mail.python.org/archives/list/security-announce@python.org/thread/KQ7NBMCPAZJHRROQXJQE4GMXGLD5KHBS/"], "threat_severity": "Low"}

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