CVE-2021-33503

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Summary

CVECVE-2021-33503
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-06-29 11:15:00 UTC
Updated2023-11-07 03:35:00 UTC
DescriptionAn 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.

Risk And Classification

Problem Types: CWE-400

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Operating System Fedoraproject Fedora 33 All All All
Operating System Fedoraproject Fedora 34 All All All
Application Oracle Enterprise Manager Ops Center 12.4.0.0 All All All
Application Oracle Instantis Enterprisetrack 17.1 All All All
Application Oracle Instantis Enterprisetrack 17.2 All All All
Application Oracle Instantis Enterprisetrack 17.3 All All All
Application Oracle Zfs Storage Appliance Kit 8.8 All All All
Application Python Urllib3 All All All All

References

ReferenceSourceLinkTags
[SECURITY] Fedora 33 Update: python-urllib3-1.25.8-5.fc33 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
[SECURITY] Fedora 34 Update: python-urllib3-1.25.10-5.fc34 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
[SECURITY] Fedora 33 Update: python-urllib3-1.25.8-5.fc33 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org
Improve performance of sub-authority splitting in URL · urllib3/urllib3@2d4a3fe · GitHub CONFIRM github.com
urllib3: Multiple vulnerabilities (GLSA 202107-36) — Gentoo security GENTOO security.gentoo.org
Catastrophic backtracking in URL authority parser when passed URL containing many @ characters · CVE-2021-33503 · GitHub Advisory Database · GitHub CONFIRM github.com
Oracle Critical Patch Update Advisory - October 2021 MISC www.oracle.com
[SECURITY] Fedora 34 Update: python-urllib3-1.25.10-5.fc34 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 159466 Oracle Enterprise Linux Security Update for python39:3.9 and python39-devel:3.9 (ELSA-2021-4160)
  • 159467 Oracle Enterprise Linux Security Update for python38:3.8 and python38-devel:3.8 (ELSA-2021-4162)
  • 180065 Debian Security Update for python-urllib3 (CVE-2021-33503)
  • 199120 Ubuntu Security Notification for urllib3 Vulnerability (USN-5812-1)
  • 239580 Red Hat Update for rh-python38 (RHSA-2021:3254)
  • 239841 Red Hat Update for python39:3.9 and python39-devel:3.9 (RHSA-2021:4160)
  • 239845 Red Hat Update for python38:3.8 and python38-devel:3.8 (RHSA-2021:4162)
  • 239895 Red Hat Update for Satellite 6.10 (RHSA-2021:4702)
  • 281655 Fedora Security Update for mingw (FEDORA-2021-b14975e43d)
  • 281676 Fedora Security Update for python (FEDORA-2021-a6bde7ab18)
  • 281699 Fedora Security Update for python (FEDORA-2021-9c5f3b8aae)
  • 296060 Oracle Solaris 11.4 Support Repository Update (SRU) 37.0.1.101.1 Missing (CPUJUL2021)
  • 352486 Amazon Linux Security Advisory for python-urllib3: ALAS2-2021-1688
  • 378599 Splunk Enterprise Third Party Package Updates for June (SVD-2023-0613)
  • 672442 EulerOS Security Update for python-pip (EulerOS-SA-2022-2854)
  • 672444 EulerOS Security Update for python-pip (EulerOS-SA-2022-2828)
  • 710032 Gentoo Linux urllib3 Multiple vulnerabilities (GLSA 202107-36)
  • 750668 SUSE Enterprise Linux Security Update for python-urllib3 (SUSE-SU-2021:2012-1)
  • 750818 OpenSUSE Security Update for python-urllib3 (openSUSE-SU-2021:2012-1)
  • 900143 CBL-Mariner Linux Security Update for python-urllib3 1.25.9
  • 901983 Common Base Linux Mariner (CBL-Mariner) Security Update for python-urllib3 (6821-1)
  • 903190 Common Base Linux Mariner (CBL-Mariner) Security Update for python-urllib3 (4373)
  • 940526 AlmaLinux Security Update for python38:3.8 and python38-devel:3.8 (ALSA-2021:4162)
  • 940559 AlmaLinux Security Update for python39:3.9 and python39-devel:3.9 (ALSA-2021:4160)
  • 960239 Rocky Linux Security Update for python39:3.9 and python39-devel:3.9 (RLSA-2021:4160)
  • 960342 Rocky Linux Security Update for python38:3.8 and python38-devel:3.8 (RLSA-2021:4162)
  • 980359 Python (pip) Security Update for urllib3 (GHSA-q2q7-5pp4-w6pg)
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