CVE-2020-5234

Name: CVE-2020-5234
Creator: NVD / NIST
Published: 2020-01-31T18:15:11.86+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 1.58%

Last modified Jun 17, 2026

CVE-2020-5234 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. 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.. EPSS estimates a 1.58% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

6.5/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

1.58%

72.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions	Update
Messagepack	Messagepack	< 1.9.3	—
Messagepack	Messagepack	>= 2.0.323, < 2.1.80	—
Messagepack	Messagepack	2.0.94	Alpha
Messagepack	Messagepack	2.0.110	Alpha
Messagepack	Messagepack	2.0.119	Beta
Messagepack	Messagepack	2.0.123	Beta
Messagepack	Messagepack	2.0.204	Beta
Messagepack	Messagepack	2.0.270	Rc
Messagepack	Messagepack	2.0.299	Rc

References

Timeline

Published: Jan 31, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-5234?

How severe is CVE-2020-5234?

CVE-2020-5234 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 1.58% probability of exploitation in the next 30 days.

How do I fix CVE-2020-5234?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-5234?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST