CVE-2021-33503
Published: 29 June 2021
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.
Notes
| Author | Note |
|---|---|
| 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 |
Priority
Status
| Package | Release | Status |
|---|---|---|
|
python-pip Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(embedded urllib3 not affected)
|
| focal |
Released
(20.0.2-5ubuntu1.7)
|
|
| groovy |
Ignored
(reached end-of-life)
|
|
| hirsute |
Ignored
(reached end-of-life)
|
|
| impish |
Not vulnerable
(20.3.4-4)
|
|
| jammy |
Not vulnerable
(20.3.4-4)
|
|
| kinetic |
Not vulnerable
(20.3.4-4)
|
|
| trusty |
Not vulnerable
(embedded urllib3 not affected)
|
|
| upstream |
Released
(21.2)
|
|
| xenial |
Not vulnerable
(embedded urllib3 not affected)
|
|
|
Patches: upstream: https://github.com/pypa/pip/commit/5394d340fb3a0b31a8e1909dd6872ecc36f75fbe (21.2) |
||
|
python-urllib3 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
|
| focal |
Released
(1.25.8-2ubuntu0.2)
|
|
| groovy |
Ignored
(reached end-of-life)
|
|
| hirsute |
Ignored
(reached end-of-life)
|
|
| impish |
Not vulnerable
(1.26.5-1~exp1)
|
|
| jammy |
Not vulnerable
(1.26.5-1~exp1)
|
|
| kinetic |
Not vulnerable
(1.26.5-1~exp1)
|
|
| trusty |
Not vulnerable
|
|
| upstream |
Released
(1.26.5)
|
|
| xenial |
Not vulnerable
|
|
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 7.5 |
| 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 |