Vulnerability Intelligence Report
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.
No Active Exploit Signals
CVSS Base Score
9.8
CRITICAL
EPSS Probability:6.83%
Executive Threat Verdict
Evaluating...
Evaluating Threat Landscape...
Assessing known weaponization, exploitation telemetry, and federal advisories.
Attack Surface
—
Authentication
—
Weaponization
—
SSVC Action
—
Affected Products & Versions
| Vendor | Product | Affected Versions |
|---|---|---|
| python | python | all |
| oracle | communications_cloud_native_core_automated_test_suite | 1.8.0 |
| oracle | communications_cloud_native_core_binding_support_function | 1.11.0 |
| oracle | communications_cloud_native_core_network_slice_selection_function | 1.8.0 |
| oracle | graalvm | 20.3.2, 21.1.0 |
| oracle | zfs_storage_appliance_kit | 8.8 |
References & Technical Advisories
No reference links found.
Threat Intelligence Signals
EPSS Score
6.827%
GitHub Advisory
Identity & Timeline
| Status | PUBLISHED |
| Assigning Authority | MITRE Corporation · N/A · USA |
| Reserved | 2021-04-01T00:00:00 |
| Published | 2021-05-06T00:00:00 |
| Last Updated | 2025-11-03T21:44:43 |
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