Vulnerability Monitor

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CVE-2021-3733


There's a flaw in urllib's AbstractBasicAuthHandler class. An attacker who controls a malicious HTTP server that an HTTP client (such as web browser) connects to, could trigger a Regular Expression Denial of Service (ReDOS) during an authentication request with a specially crafted payload that is sent by the server to the client. The greatest threat that this flaw poses is to application availability.


Security Impact Summary

This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 6.5, indicating it can be exploited remotely over the network with relatively low complexity without requiring user interaction requiring only low-level privileges . The vulnerability impacts and availability (service disruption) for affected systems. Impacting 20 products from python, from redhat, from redhat and 17 others, organizations running these solutions should prioritize assessment and patching.

Historical Context

Reported in 2022, this vulnerability emerged during an era marked by increased sophistication in supply chain attacks, cloud infrastructure vulnerabilities, and software-as-a-service (SaaS) security challenges. Security practices during this period emphasized zero-trust architectures, container security, and API protection.


Published

2022-03-10T17:42:59.623

Last Modified

2025-11-03T22:15:50.833

Status

Modified

Source

[email protected]

Severity

CVSSv3.1: 6.5 (MEDIUM)

CVSSv2 Vector

AV:N/AC:L/Au:S/C:N/I:N/A:P

  • Access Vector: NETWORK
  • Access Complexity: LOW
  • Authentication: SINGLE
  • Confidentiality Impact: NONE
  • Integrity Impact: NONE
  • Availability Impact: PARTIAL
Exploitability Score

8.0

Impact Score

2.9

Weaknesses
  • Type: Secondary
    CWE-400
  • Type: Primary
    CWE-400

Affected Vendors & Products
Type Vendor Product Version/Range Vulnerable?
Application python python < 3.6.14 Yes
Application python python < 3.7.11 Yes
Application python python < 3.8.10 Yes
Application python python < 3.9.5 Yes
Application python python 3.10.0 Yes
Application redhat codeready_linux_builder 8.0 Yes
Application redhat codeready_linux_builder_for_ibm_z_systems 8.0 Yes
Application redhat codeready_linux_builder_for_power_little_endian 8.0 Yes
Operating System redhat enterprise_linux 8.0 Yes
Operating System redhat enterprise_linux_eus 8.4 Yes
Operating System redhat enterprise_linux_for_ibm_z_systems 8.0 Yes
Operating System redhat enterprise_linux_for_ibm_z_systems_eus 8.4 Yes
Operating System redhat enterprise_linux_for_power_little_endian 8.0 Yes
Operating System redhat enterprise_linux_for_power_little_endian_eus 8.4 Yes
Operating System redhat enterprise_linux_server_aus 8.4 Yes
Operating System redhat enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions 8.4 Yes
Operating System redhat enterprise_linux_server_tus 8.4 Yes
Operating System redhat enterprise_linux_server_update_services_for_sap_solutions 8.4 Yes
Application fedoraproject extra_packages_for_enterprise_linux 7.0 Yes
Operating System fedoraproject fedora 33 Yes
Operating System fedoraproject fedora 34 Yes
Operating System fedoraproject fedora 35 Yes
Operating System fedoraproject fedora 36 Yes
Application netapp management_services_for_element_software_and_netapp_hci - Yes
Application netapp ontap_select_deploy_administration_utility - Yes
Application netapp solidfire\,_enterprise_sds_\&_hci_storage_node - Yes
Operating System netapp hci_compute_node_firmware - Yes

References

How SecUtils Interprets This CVE

SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For python's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.