CVE-2021-3177

9.8 CRITICAL
Published: January 19, 2021 Modified: December 18, 2025
View on NVD

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.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://bugs.python.org/issue42938
Source: cve@mitre.org
Exploit Issue Tracking Patch Vendor Advisory
https://github.com/python/cpython/pull/24239
Source: cve@mitre.org
Patch Third Party Advisory
https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3E
Source: cve@mitre.org
https://lists.debian.org/debian-lts-announce/2021/04/msg00005.html
Source: cve@mitre.org
Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/02/msg00013.html
Source: cve@mitre.org
Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2023/05/msg00024.html
Source: cve@mitre.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BRHOCQYX3QLDGDQGTWQAUUT2GGIZCZUO/
Source: cve@mitre.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CCFZMVRQUKCBQIG5F2CBVADK63NFSE4A/
Source: cve@mitre.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FONHJIOZOFD7CD35KZL6SVBUTMBPGZGA/
Source: cve@mitre.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FPE7SMXYUIWPOIZV4DQYXODRXMFX3C5E/
Source: cve@mitre.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HCQTCSP6SCVIYNIRUJC5X7YBVUHPLSC4/
Source: cve@mitre.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MGSV6BJQLRQ6RKVUXK7JGU7TP4QFGQXC/
Source: cve@mitre.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MP572OLHMS7MZO4KUPSCIMSZIA5IZZ62/
Source: cve@mitre.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NODWHDIFBQE5RU5PUWUVE47JOT5VCMJ2/
Source: cve@mitre.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NQPARTLNSFQVMMQHPNBFOCOZOO3TMQNA/
Source: cve@mitre.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NXSMBHES3ANXXS2RSO5G6Q24BR4B2PWK/
Source: cve@mitre.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/V6XJAULOS5JVB2L67NCKKMJ5NTKZJBSD/
Source: cve@mitre.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Y4KSYYWMGAKOA2JVCQA422OINT6CKQ7O/
Source: cve@mitre.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YDTZVGSXQ7HR7OCGSUHTRNTMBG43OMKU/
Source: cve@mitre.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Z7GZV74KM72O2PEJN2C4XP3V5Q5MZUOO/
Source: cve@mitre.org
https://news.ycombinator.com/item?id=26185005
Source: cve@mitre.org
Third Party Advisory
https://python-security.readthedocs.io/vuln/ctypes-buffer-overflow-pycarg_repr.html
Source: cve@mitre.org
Patch Third Party Advisory
https://security.gentoo.org/glsa/202101-18
Source: cve@mitre.org
Third Party Advisory
https://security.netapp.com/advisory/ntap-20210226-0003/
Source: cve@mitre.org
Third Party Advisory
https://www.oracle.com//security-alerts/cpujul2021.html
Source: cve@mitre.org
Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpujan2022.html
Source: cve@mitre.org
Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpujul2022.html
Source: cve@mitre.org
Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpuoct2021.html
Source: cve@mitre.org
Patch Third Party Advisory
https://bugs.python.org/issue42938
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Issue Tracking Patch Vendor Advisory
https://github.com/python/cpython/pull/24239
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3E
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.debian.org/debian-lts-announce/2021/04/msg00005.html
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/02/msg00013.html
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2023/05/msg00024.html
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BRHOCQYX3QLDGDQGTWQAUUT2GGIZCZUO/
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CCFZMVRQUKCBQIG5F2CBVADK63NFSE4A/
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FONHJIOZOFD7CD35KZL6SVBUTMBPGZGA/
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FPE7SMXYUIWPOIZV4DQYXODRXMFX3C5E/
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HCQTCSP6SCVIYNIRUJC5X7YBVUHPLSC4/
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MGSV6BJQLRQ6RKVUXK7JGU7TP4QFGQXC/
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MP572OLHMS7MZO4KUPSCIMSZIA5IZZ62/
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NODWHDIFBQE5RU5PUWUVE47JOT5VCMJ2/
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NQPARTLNSFQVMMQHPNBFOCOZOO3TMQNA/
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NXSMBHES3ANXXS2RSO5G6Q24BR4B2PWK/
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/V6XJAULOS5JVB2L67NCKKMJ5NTKZJBSD/
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Y4KSYYWMGAKOA2JVCQA422OINT6CKQ7O/
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YDTZVGSXQ7HR7OCGSUHTRNTMBG43OMKU/
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Z7GZV74KM72O2PEJN2C4XP3V5Q5MZUOO/
Source: af854a3a-2127-422b-91ae-364da2661108
https://news.ycombinator.com/item?id=26185005
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://python-security.readthedocs.io/vuln/ctypes-buffer-overflow-pycarg_repr.html
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://security.gentoo.org/glsa/202101-18
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://security.netapp.com/advisory/ntap-20210226-0003/
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://www.oracle.com//security-alerts/cpujul2021.html
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpujan2022.html
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpujul2022.html
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpuoct2021.html
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory

56 reference(s) from NVD

Quick Stats

CVSS v3 Score
9.8 / 10.0
EPSS (Exploit Probability)
0.1%
22th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

CWE-120 CWE-120

Affected Vendors

python fedoraproject netapp oracle debian

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