CVE-2021-33503

Publication date 29 June 2021

Last updated 24 July 2024


Ubuntu priority

Cvss 3 Severity Score

7.5 · High

Score breakdown

An issue was discovered in urllib3 before 1.26.5. When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.

Read the notes from the security team

Status

Package Ubuntu Release Status
python-pip 22.10 kinetic
Not affected
22.04 LTS jammy
Not affected
21.10 impish
Not affected
21.04 hirsute Ignored end of life
20.10 groovy Ignored end of life
20.04 LTS focal
Fixed 20.0.2-5ubuntu1.7
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected
python-urllib3 22.10 kinetic
Not affected
22.04 LTS jammy
Not affected
21.10 impish
Not affected
21.04 hirsute Ignored end of life
20.10 groovy Ignored end of life
20.04 LTS focal
Fixed 1.25.8-2ubuntu0.2
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected

Notes


mdeslaur

the python-pip package bundles python-urllib3 binaries when built. After updating python-urllib3, a no-change rebuild of python-pip is required.


sbeattie

python-pip 20.3.4-4 build in impish is built against python3-urllib3 1.26.5-1~exp1, and thus impish and newer is fixed. introduced in urllib3 in 0aa3e24fcd75f1bb59ab159e9f8adb44055b2271 or newer

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
python-pip

Severity score breakdown

Parameter Value
Base score 7.5 · High
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Scope Unchanged
Confidentiality None
Integrity impact None
Availability impact High
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H