CVE-2021-3737

7.5 HIGH
Published: March 04, 2022 Modified: December 17, 2025
View on NVD

Description

A flaw was found in python. An improperly handled HTTP response in the HTTP client code of python may allow a remote attacker, who controls the HTTP server, to make the client script enter an infinite loop, consuming CPU time. The highest threat from this vulnerability is to system availability.

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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:N/I:N/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://bugs.python.org/issue44022
Source: secalert@redhat.com
Exploit Issue Tracking Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1995162
Source: secalert@redhat.com
Issue Tracking Patch Third Party Advisory
https://github.com/python/cpython/pull/25916
Source: secalert@redhat.com
Patch Third Party Advisory
https://github.com/python/cpython/pull/26503
Source: secalert@redhat.com
Patch Third Party Advisory
https://lists.debian.org/debian-lts-announce/2023/05/msg00024.html
Source: secalert@redhat.com
https://lists.debian.org/debian-lts-announce/2023/06/msg00039.html
Source: secalert@redhat.com
https://python-security.readthedocs.io/vuln/urllib-100-continue-loop.html
Source: secalert@redhat.com
Patch Third Party Advisory
https://security.netapp.com/advisory/ntap-20220407-0009/
Source: secalert@redhat.com
Third Party Advisory
https://ubuntu.com/security/CVE-2021-3737
Source: secalert@redhat.com
Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpujul2022.html
Source: secalert@redhat.com
Patch Third Party Advisory
https://bugs.python.org/issue44022
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Issue Tracking Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1995162
Source: af854a3a-2127-422b-91ae-364da2661108
Issue Tracking Patch Third Party Advisory
https://github.com/python/cpython/pull/25916
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://github.com/python/cpython/pull/26503
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://lists.debian.org/debian-lts-announce/2023/05/msg00024.html
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.debian.org/debian-lts-announce/2023/06/msg00039.html
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.debian.org/debian-lts-announce/2024/11/msg00024.html
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.debian.org/debian-lts-announce/2024/12/msg00000.html
Source: af854a3a-2127-422b-91ae-364da2661108
https://python-security.readthedocs.io/vuln/urllib-100-continue-loop.html
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://security.netapp.com/advisory/ntap-20220407-0009/
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://ubuntu.com/security/CVE-2021-3737
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

22 reference(s) from NVD

Quick Stats

CVSS v3 Score
7.5 / 10.0
EPSS (Exploit Probability)
0.2%
38th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

CWE-835 CWE-400 CWE-835

Affected Vendors

redhat canonical python fedoraproject netapp oracle

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