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VULNERABILITIES

CVE-2021-33503 Details

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.

Metrics

CVSS 3.x Severity and Vector Strings:

NIST: [email protected]CVSS-B:7.5 HIGHVector:CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References to Advisories, Solutions, and Tools

By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.

URLSource(s)Tag(s)
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg CVEThird Party Advisory
https://github.com/urllib3/urllib3/commit/2d4a3fee6de2fa45eb82169361918f759269b4ec CVEPatchThird Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6SCV7ZNAHS3E6PBFLJGENCDRDRWRZZ6W/ CVE
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FMUGWEAUYGGHTPPXT6YBD53WYXQGVV73/ CVE
https://security.gentoo.org/glsa/202107-36 CVEThird Party Advisory

see all 12 references

Weakness Enumeration

CWE-IDCWE NameSource
CWE-400Uncontrolled Resource Consumption[email protected]

Affected Products

ProductVersions
python urllib3
>= 1.25.4, < 1.26.5

CPE

  • cpe:2.3:a:python:urllib3:*:*:*:*:*:*:*:*

Remediation

  • No remediation found in references.
fedoraproject fedora
33
34

CPE

  • cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
  • cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*

Remediation

  • No remediation found in references.
oracle enterprise manager ops center
12.4.0.0

CPE

  • cpe:2.3:a:oracle:enterprise_manager_ops_center:12.4.0.0:*:*:*:*:*:*:*

Remediation

  • No remediation found in references.
oracle instantis enterprisetrack
17.1
17.2
17.3

CPE

  • cpe:2.3:a:oracle:instantis_enterprisetrack:17.1:*:*:*:*:*:*:*
  • cpe:2.3:a:oracle:instantis_enterprisetrack:17.2:*:*:*:*:*:*:*
  • cpe:2.3:a:oracle:instantis_enterprisetrack:17.3:*:*:*:*:*:*:*

Remediation

  • No remediation found in references.
oracle zfs storage appliance kit
8.8

CPE

  • cpe:2.3:a:oracle:zfs_storage_appliance_kit:8.8:*:*:*:*:*:*:*

Remediation

  • No remediation found in references.

Change History

13 change records found show changes

QUICK INFO

CVE Dictionary Entry:
CVE-2021-33503
NVD Published Date:
Jun 29, 2021
NVD Last Modified:
Jun 17, 2026
Source:
[email protected]
CVE-2021-33503 Details - Not Deferred