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CVE-2020-5234
Published:January 31, 2020
Updated:May 17, 2026
MessagePack for C# and Unity before version 1.9.11 and 2.1.90 has a vulnerability where untrusted data can lead to DoS attack due to hash collisions and stack overflow. Review the linked GitHub Security Advisory for more information and remediation steps.
Affected Packages
messagepack (NUGET):
Affected version(s) >=0.1.0-beta <1.9.11
Fix Suggestion:
Update to version 1.9.11
messagepack.immutablecollection (NUGET):
Affected version(s) >=0.2.0-beta <1.9.11
Fix Suggestion:
Update to version 1.9.11
messagepack.immutablecollection (NUGET):
Affected version(s) >=2.0.107-alpha <2.1.90
Fix Suggestion:
Update to version 2.1.90
messagepack.reactiveproperty (NUGET):
Affected version(s) >=2.0.107-alpha <2.1.90
Fix Suggestion:
Update to version 2.1.90
messagepack (NUGET):
Affected version(s) >=2.0.107-alpha <2.1.90
Fix Suggestion:
Update to version 2.1.90
messagepack.reactiveproperty (NUGET):
Affected version(s) >=0.1.0-beta <1.9.11
Fix Suggestion:
Update to version 1.9.11
messagepack.unityshims (NUGET):
Affected version(s) >=0.6.0 <1.9.11
Fix Suggestion:
Update to version 1.9.11
messagepack.unityshims (NUGET):
Affected version(s) >=2.0.107-alpha <2.1.90
Fix Suggestion:
Update to version 2.1.90
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CVSS v4
Base Score:
5.9
Attack Vector
NETWORK
Attack Complexity
HIGH
Attack Requirements
NONE
Privileges Required
LOW
User Interaction
PASSIVE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
NONE
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
4.8
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
LOW
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Weakness Type (CWE)
Out-of-bounds Write
Stack-based Buffer Overflow
EPSS
Base Score:
0.55