CVE-2021-29921
CRITICAL
9.8
CVSS Score
Published: May 6, 2021 at 12:00 AM UTC
Updated: October 8, 2026 at 10:17 PM UTC
6 products affected across 2 vendorsPythonGraalVMZfs Storage Appliance Kit
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Severity
CRITICAL9.8
Exploit prediction
EPSS 7%
SSVC
No known exploit
Description
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.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
References (17)
ExploitThird Party Advisory
Source: [email protected]
https://github.com/sickcodes/security/blob/master/advisories/SICK-2021-014.mdSSVC — Action Prioritization
SSVCNo known exploitAutomatableTotal impact
SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.
CVSS
- Attack Vector
- NETWORK
- Complexity
- LOW
- Privileges
- NONE
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality
- HIGH
- Integrity
- HIGH
- Availability
- HIGH
Vector?
Quick Info
StatusMODIFIED
CWE
NVD-CWE-Other
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