Vulnerability Monitor

The vendors, products, and vulnerabilities you care about

CVE-2021-29921


In Python before 3,9,5, the ipaddress library mishandles leading zero characters in the octets of an IP address string. This (in some situations) allows attackers to bypass access control that is based on IP addresses.


Security Impact Summary

This vulnerability carries a CRITICAL severity rating with a CVSS v3.1 score of 9.8, indicating it can be exploited remotely over the network with relatively low complexity without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts confidentiality (data exposure), integrity (unauthorized modifications), and availability (service disruption) for affected systems. Impacting 6 products from python, from oracle, from oracle and 3 others, organizations running these solutions should prioritize assessment and patching.

Historical Context

Reported in 2021, 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

2021-05-06T13:15:12.573

Last Modified

2025-11-03T22:15:48.057

Status

Modified

Source

[email protected]

Severity

CVSSv3.1: 9.8 (CRITICAL)

CVSSv2 Vector

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

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

10.0

Impact Score

6.4

Weaknesses
  • Type: Primary
    NVD-CWE-Other

Affected Vendors & Products
Type Vendor Product Version/Range Vulnerable?
Application python python < 3.8.12 Yes
Application python python < 3.9.5 Yes
Application oracle communications_cloud_native_core_automated_test_suite 1.8.0 Yes
Application oracle communications_cloud_native_core_binding_support_function 1.11.0 Yes
Application oracle communications_cloud_native_core_network_slice_selection_function 1.8.0 Yes
Application oracle graalvm 20.3.2 Yes
Application oracle graalvm 21.1.0 Yes
Application oracle zfs_storage_appliance_kit 8.8 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.