USN-5200-1: Python vulnerabilities

Releases

• Ubuntu 18.04 ESM

Packages

• python3.7 - An interactive high-level object-oriented language
• python3.8 - An interactive high-level object-oriented language

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 a client.
(CVE-2021-3737)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 18.04

• 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

In general, a standard system update will make all the necessary changes.

References

• CVE-2021-3737
• CVE-2020-8492
• CVE-2021-3733

Related notices

• USN-5083-1: libpython3.5, python3.4-dev, idle-python3.5, python3.5, python3.5-examples, python3.4-doc, libpython3.4-testsuite, libpython3.5-testsuite, libpython3.5-stdlib, python3.5-venv, libpython3.4-minimal, libpython3.5-minimal, python3.4-examples, idle-python3.4, python3.5-doc, libpython3.4, python3.5-minimal, python3.5-dev, libpython3.4-dev, libpython3.5-dev, libpython3.4-stdlib, python3.4-minimal, python3.4-venv, python3.4
• USN-5199-1: libpython3.6-testsuite, python3.6-examples, libpython3.6, libpython3.6-stdlib, python3.6-dev, python3.6-doc, libpython3.6-dev, python3.6-venv, idle-python3.6, python3.6-minimal, python3.6, libpython3.6-minimal
• USN-5201-1: libpython3.8-stdlib, libpython3.9-dev, python3.9-dev, libpython3.9-testsuite, python3.8-dev, python3.9, libpython3.8-testsuite, libpython3.8-dev, python3.9-full, python3.8-examples, python3.9-minimal, python3.9-doc, libpython3.9, python3.8-doc, python3.8-full, python3.8-venv, libpython3.8, libpython3.9-minimal, libpython3.9-stdlib, python3.8, idle-python3.8, idle-python3.9, libpython3.8-minimal, python3.8-minimal, python3.9-venv, python3.9-examples
• USN-4333-1: libpython3.5, python2.7, python3.4-dev, idle-python3.5, python3.5, python3.5-examples, python3.6-venv, libpython3.7-stdlib, libpython3.4-testsuite, python3.4-doc, libpython3.5-testsuite, libpython3.6-testsuite, idle-python3.6, libpython3.5-stdlib, python3.6-doc, python3.5-venv, python3.7, libpython3.7-minimal, python3.7-minimal, libpython3.5-minimal, python3.6, python3.4-examples, libpython3.7, libpython2.7-dev, idle-python2.7, python2.7-minimal, python3.7-doc, idle-python3.4, python2.7-doc, libpython3.4, python3.5-doc, python3.5-minimal, libpython3.7-dev, python3.6-dev, libpython3.6-dev, libpython2.7, python3.7-examples, python2.7-dev, python3.7-venv, libpython3.6-minimal, python3.4-venv, python3.5-dev, libpython3.4-dev, libpython3.7-testsuite, python3.7-dev, python3.6-examples, libpython3.6, libpython3.6-stdlib, libpython3.5-dev, libpython2.7-testsuite, python2.7-examples, libpython3.4-stdlib, python3.4-minimal, libpython2.7-minimal, libpython3.4-minimal, idle-python3.7, libpython2.7-stdlib, python3.6-minimal, python3.4
• USN-4333-2: idle-python3.8, libpython3.8-testsuite, libpython3.8-stdlib, libpython3.8-dev, libpython3.8-minimal, python3.8-examples, python3.8-minimal, python3.8-doc, python3.8, python3.8-venv, libpython3.8, python3.8-dev
• USN-4754-3: libpython3.8-stdlib, python2.7, libpython3.7-stdlib, python3.8-dev, libpython3.8-testsuite, libpython3.8-dev, python3.8-examples, python3.7, libpython3.7-minimal, python3.8-venv, libpython3.8, python3.7-minimal, libpython3.7, libpython2.7-dev, idle-python2.7, python2.7-minimal, python3.7-doc, python2.7-doc, python3.7-examples, libpython3.7-dev, python3.8, libpython2.7, python2.7-dev, python3.7-venv, idle-python3.8, libpython3.7-testsuite, python3.7-dev, libpython3.8-minimal, python3.8-minimal, libpython2.7-testsuite, python2.7-examples, libpython2.7-minimal, idle-python3.7, libpython2.7-stdlib