USN-5200-1: Python vulnerabilities
Publication date
17 December 2021
Overview
Python could be made to crash if it receives specially crafted input from a malicious server.
Releases
Packages
Details
It was discovered that the urllib.request.AbstractBasicAuthHandler class
in Python contains regex allowing for catastrophic backtracking. Specially
crafted traffic from a malicious HTTP server could cause a regular expression
denial of service (ReDoS) condition for a client.
(CVE-2020-8492)
It was discovered that the urllib.request.AbstractBasicAuthHandler class
in Python contains regex with a quadratic worst-case time complexity.
Specially crafted traffic from a malicious HTTP server could cause a regular
expression denial of service (ReDoS) condition for a client.
(CVE-2021-3733)
It was discovered that the Python urllib http client could enter into an infinite
loop when incorrectly handling certain server responses (100 Continue response).
Specially crafted traffic from a malicious HTTP server could cause a denial of
service (DoS) condition for...
It was discovered that the urllib.request.AbstractBasicAuthHandler class
in Python contains regex allowing for catastrophic backtracking. Specially
crafted traffic from a malicious HTTP server could cause a regular expression
denial of service (ReDoS) condition for a client.
(CVE-2020-8492)
It was discovered that the urllib.request.AbstractBasicAuthHandler class
in Python contains regex with a quadratic worst-case time complexity.
Specially crafted traffic from a malicious HTTP server could cause a regular
expression denial of service (ReDoS) condition for a client.
(CVE-2021-3733)
It was discovered that the Python urllib http client could enter into an infinite
loop when incorrectly handling certain server responses (100 Continue response).
Specially crafted traffic from a malicious HTTP server could cause a denial of
service (DoS) condition for a client.
(CVE-2021-3737)
Update instructions
In general, a standard system update will make all the necessary changes.
Learn more about how to get the fixes.The problem can be corrected by updating your system to the following package versions:
| Ubuntu Release | Package Version | ||
|---|---|---|---|
| 18.04 bionic | python3.7-minimal – 3.7.5-2ubuntu1~18.04.2 | ||
| libpython3.8-stdlib – 3.8.0-3ubuntu1~18.04.2 | |||
| libpython3.7-stdlib – 3.7.5-2ubuntu1~18.04.2 | |||
| python3.7 – 3.7.5-2ubuntu1~18.04.2 | |||
| python3.8 – 3.8.0-3ubuntu1~18.04.2 | |||
| python3.8-minimal – 3.8.0-3ubuntu1~18.04.2 | |||
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