Critical severity · published Jan 19, 2021
CVE-2021-3177
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…
9.8
CVSS
24.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)24.2% · higher than 98% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AI
Active IQ Unified Manager · Netapp
All versions, or not specified · source: NVD
CC
CO
Communications Offline Mediation Controller · Oracle
12.0.0.3.0 · source: NVD
CP
Communications Pricing Design Center · Oracle
12.0.0.3.0 · source: NVD
DL
Debian Linux · Debian
9.0 · source: NVD
EM
Enterprise Manager Ops Center · Oracle
12.4.0.0 · source: NVD
FE
Fedora · Fedoraproject
32; 33 · source: NVD
OS
Ontap Select Deploy Administration Utility · Netapp
All versions, or not specified · source: NVD
PY
Python · Python
3.6.0 through 3.6.12; 3.7.0 through 3.7.9; 3.8.0 through 3.8.7; 3.9.0 through 3.9.1 · source: NVD
ZS
Zfs Storage Appliance Kit · Oracle
8.8 · source: NVD
SS
SIMATIC S7-1500 CPU 1518-4 PN/DP MFP · Siemens
V3.1.0 before V3.1.5; V3.1.0 before V3.1.5 · source: CISA
SS
SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP · Siemens
V3.1.0 before V3.1.5; V3.1.0 before V3.1.5 · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-3177
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-3177
Exploit
https://bugs.python.org/issue42938
Patch
https://github.com/python/cpython/pull/24239
lists.apache.org
https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3E
Mailing List
https://lists.debian.org/debian-lts-announce/2021/04/msg00005.html
Mailing List
https://lists.debian.org/debian-lts-announce/2022/02/msg00013.html
lists.debian.org
https://lists.debian.org/debian-lts-announce/2023/05/msg00024.html
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