What is CVE-2026-48510?

CVE-2026-48510 is a high-severity vulnerability in Messagepack, classified under Improper Handling of Highly Compressed Data (Data Amplification). CVSS score: 7.5/10. Published 2026-06-22.

How severe is CVE-2026-48510?

High severity. CVSS v3 base score is 7.5 out of 10.

Resource exhaustion in Messagepack

CVE-2026-48510

MessagePack for C# is a MessagePack serializer for C#. Prior to 2.5.301 and 3.1.7, when MessagePack-CSharp decompresses Lz4Block or Lz4BlockArray payloads, it reads declared uncompressed lengths from the wire and allocates output buffers b…

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Messagepack
Messagepack-csharp — versions >= 3.1.7, < 3.1.7, < 2.5.301

Weakness classification (CWE)

CWE-409 — Improper Handling of Highly Compressed Data (Data Amplification)
CWE-770 — Allocation of Resources Without Limits or Throttling

References

security-advisories@github.com (x_refsource_CONFIRM, Mitigation, Vendor Advisory)

Frequently asked questions

What is CVE-2026-48510?: CVE-2026-48510 is a high-severity vulnerability in Messagepack, classified under Improper Handling of Highly Compressed Data (Data Amplification). CVSS score: 7.5/10. Published 2026-06-22.
How severe is CVE-2026-48510?: High severity. CVSS v3 base score is 7.5 out of 10.