CVE-2021-3177

CRITICAL

Python < 3.6.12 - Buffer Overflow

Title source: rule
STIX 2.1

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.

References (28)

Core 28
Core References
Mailing List, Third Party Advisory mailing-list
https://lists.debian.org/debian-lts-announce/2021/04/msg00005.html
Mailing List, Third Party Advisory mailing-list
https://lists.debian.org/debian-lts-announce/2022/02/msg00013.html
Exploit, Issue Tracking, Patch, Vendor Advisory
https://bugs.python.org/issue42938
Patch, Third Party Advisory
https://github.com/python/cpython/pull/24239
Third Party Advisory vendor-advisory
https://security.gentoo.org/glsa/202101-18

Scores

CVSS v3 9.8
EPSS 0.0007
EPSS Percentile 21.6%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation poc
Automatable yes
Technical Impact total

Details

CWE
CWE-120
Status published
Products (11)
debian/debian_linux 9.0
fedoraproject/fedora 32
fedoraproject/fedora 33
netapp/active_iq_unified_manager (2 CPE variants)
netapp/ontap_select_deploy_administration_utility
oracle/communications_cloud_native_core_network_function_cloud_native_environment 22.2.0
oracle/communications_offline_mediation_controller 12.0.0.3.0
oracle/communications_pricing_design_center 12.0.0.3.0
oracle/enterprise_manager_ops_center 12.4.0.0
oracle/zfs_storage_appliance_kit 8.8
... and 1 more
Published Jan 19, 2021
Tracked Since Feb 18, 2026