CVE-2021-33503

high

Description

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.

References

Advisories

https://www.oracle.com/security-alerts/cpuoct2021.html

https://security.gentoo.org/glsa/202107-36

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FMUGWEAUYGGHTPPXT6YBD53WYXQGVV73/

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6SCV7ZNAHS3E6PBFLJGENCDRDRWRZZ6W/

https://github.com/urllib3/urllib3/commit/2d4a3fee6de2fa45eb82169361918f759269b4ec

https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

Details

Source: Mitre, NVD

Published: 2021-06-29

Updated: 2023-11-07

Risk Information

CVSS v2

Base Score: 5

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

Severity: Medium

CVSS v3

Base Score: 7.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Severity: High

CVSS v4

Base Score: 8.7

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Severity: High

EPSS

EPSS: 0.00863