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CVE-2021-33318
Published:May 16, 2022
Updated:July 21, 2026
An Input Validation Vulnerability exists in Joel Christner .NET C# packages WatsonWebserver, IpMatcher 1.0.4.1 and below (IpMatcher) and 4.1.3 and below (WatsonWebserver) due to insufficient validation of input IP addresses and netmasks against the internal Matcher list of IP addresses and subnets.
Affected Packages
ipmatcher (NUGET):
Affected version(s) >=1.0.0 <1.0.4.2
Fix Suggestion:
Update to version 1.0.4.2
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CVSS v4
Base Score:
9.3
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
9.8
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Weakness Type (CWE)
Incorrect Type Conversion or Cast
Improper Input Validation
EPSS
Base Score:
1.96