{"id":"CVE-2021-3177","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-3177","generatedAt":"2026-11-05T01:47:33.402Z","title":"Python 3.x through 3.9.1 has a buffer overflow in PyCArg_repr in _ctypes/callproc.c, which may lead to remote code execution in certain Python applications that accept floating-point numbers as untrusted input, as demonstrated by a 1e300 argument to…","description":"Python 3.x through 3.9.1 has a buffer overflow in PyCArg_repr in _ctypes/callproc.c, which may lead to remote code execution in certain Python applications that accept floating-point numbers as untrusted input, as demonstrated by a 1e300 argument to c_double.from_param. This occurs because sprintf is used unsafely.","published":"2021-01-19T06:15:13.000Z","lastModified":"2026-10-14T10:17:38.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.1","score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-120"],"affected":["python/python","fedoraproject/fedora","netapp/active iq unified manager","netapp/ontap select deploy administration utility","debian/debian linux","oracle/communications cloud native core network function cloud native environment","oracle/communications offline mediation controller","oracle/communications pricing design center","oracle/enterprise manager ops center","oracle/zfs storage appliance kit"],"epss":{"score":0.24002,"percentile":0.97844,"date":"2026-11-03","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"urgent","text":"EPSS puts the probability of exploitation in the next 30 days at 24.0%, higher than 98% of all known CVEs. Patch or mitigate before the next change window."},"changes":[],"references":[{"url":"https://bugs.python.org/issue42938","tags":["Exploit","Issue Tracking","Patch","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/python/cpython/pull/24239","tags":["Patch","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3E","source":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2021/04/msg00005.html","tags":["Mailing List","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2022/02/msg00013.html","tags":["Mailing List","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2023/05/msg00024.html","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BRHOCQYX3QLDGDQGTWQAUUT2GGIZCZUO/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CCFZMVRQUKCBQIG5F2CBVADK63NFSE4A/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FONHJIOZOFD7CD35KZL6SVBUTMBPGZGA/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FPE7SMXYUIWPOIZV4DQYXODRXMFX3C5E/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HCQTCSP6SCVIYNIRUJC5X7YBVUHPLSC4/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MGSV6BJQLRQ6RKVUXK7JGU7TP4QFGQXC/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MP572OLHMS7MZO4KUPSCIMSZIA5IZZ62/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NODWHDIFBQE5RU5PUWUVE47JOT5VCMJ2/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NQPARTLNSFQVMMQHPNBFOCOZOO3TMQNA/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NXSMBHES3ANXXS2RSO5G6Q24BR4B2PWK/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/V6XJAULOS5JVB2L67NCKKMJ5NTKZJBSD/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Y4KSYYWMGAKOA2JVCQA422OINT6CKQ7O/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YDTZVGSXQ7HR7OCGSUHTRNTMBG43OMKU/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Z7GZV74KM72O2PEJN2C4XP3V5Q5MZUOO/","source":"cve@mitre.org"},{"url":"https://news.ycombinator.com/item?id=26185005","tags":["Third 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