PT-2020-6268 · Python+9 · Python+9

Ben Caller

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Published

2020-01-30

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Updated

2026-05-18

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CVE-2020-8492

CVSS v2.0

7.1

High

VectorAV:N/AC:M/Au:N/C:N/I:N/A:C
Name of the Vulnerable Software and Affected Versions Python versions 2.7 through 2.7.17 Python versions 3.5 through 3.5.9 Python versions 3.6 through 3.6.10 Python versions 3.7 through 3.7.6 Python versions 3.8 through 3.8.1
Description The issue is related to an uncontrolled consumption of resources in the Python interpreter. It allows an HTTP server to conduct Regular Expression Denial of Service (ReDoS) attacks against a client because of urllib.request.AbstractBasicAuthHandler catastrophic backtracking. This can be exploited by a remote attacker to cause a denial of service.
Recommendations For Python versions 2.7 through 2.7.17, consider disabling the urllib.request.AbstractBasicAuthHandler to minimize the risk of exploitation until a patch is available. For Python versions 3.5 through 3.5.9, consider disabling the urllib.request.AbstractBasicAuthHandler to minimize the risk of exploitation until a patch is available. For Python versions 3.6 through 3.6.10, consider disabling the urllib.request.AbstractBasicAuthHandler to minimize the risk of exploitation until a patch is available. For Python versions 3.7 through 3.7.6, consider disabling the urllib.request.AbstractBasicAuthHandler to minimize the risk of exploitation until a patch is available. For Python versions 3.8 through 3.8.1, consider disabling the urllib.request.AbstractBasicAuthHandler to minimize the risk of exploitation until a patch is available. As a temporary workaround, consider restricting access to the vulnerable urllib.request module to minimize the risk of exploitation.

Exploit

Fix

DoS

Resource Exhaustion

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Weakness Enumeration

Related Identifiers

ALSA-2020:4641
ALT-PU-2020-1597
ALT-PU-2020-1914
ALT-PU-2020-3318
ALT-PU-2020-3323
ALT-PU-2021-2653
ALT-PU-2024-3474
BDU:2021-03740
BIT-LIBPYTHON-2020-8492
BIT-PYTHON-2020-8492
BIT-PYTHON-MIN-2020-8492
CESA-2020_3888
CESA-2020_4433
CESA-2020_4641
CLEANSTART-2026-BM51903
CLEANSTART-2026-SY44974
CVE-2020-8492
DLA-2280-1
DLA-3432-1
MGASA-2020-0451
OPENSUSE-SU-2020:0274-1
OPENSUSE-SU-2020:2332-1
OPENSUSE-SU-2020:2333-1
OPENSUSE-SU-2020_0274-1
OPENSUSE-SU-2020_2332-1
OPENSUSE-SU-2020_2333-1
OPENSUSE-SU-2022_4281-1
OPENSUSE-SU-2024:11202-1
OPENSUSE-SU-2024:11283-1
OPENSUSE-SU-2024:11284-1
OPENSUSE-SU-2024:11285-1
OPENSUSE-SU-2024:11286-1
OPENSUSE-SU-2024:12089-1
OPENSUSE-SU-2024:12910-1
OPENSUSE-SU-2024:14109-1
OPENSUSE-SU-2024:14434-1
OPENSUSE-SU-2025:15713-1
PSF-2020-8
RHSA-2020:3888
RHSA-2020:4285
RHSA-2020:4433
RHSA-2020:4641
RHSA-2020_3888
RHSA-2020_4433
RHSA-2020_4641
RLSA-2020:4641
ROSA-SA-2025-2646
SUSE-FU-2022:0444-1
SUSE-FU-2022:0445-1
SUSE-SU-2020:0467-1
SUSE-SU-2020:0510-1
SUSE-SU-2020:0557-1
SUSE-SU-2020:0854-1
SUSE-SU-2020:14306-1
SUSE-SU-2020:1524-1
SUSE-SU-2020:3563-1
SUSE-SU-2020:3865-1
SUSE-SU-2020:3930-1
SUSE-SU-2020_14306-1
SUSE-SU-2020_1524-1
SUSE-SU-2022:4281-1
USN-4333-1
USN-4333-2
USN-4754-3
USN-5200-1
USN-6891-1

Affected Products

Alt Linux
Almalinux
Astra Linux
Centos
Linuxmint
Python
Red Hat
Rocky Linux
Suse
Ubuntu