CVE-2026-48510: MessagePack-CSharp: LZ4 decompression allocates from unbounded declared output lengths
Affected: MessagePack-CSharp · Exploitation: unlikely (under 1%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Percentile not published
DescriptionCVE.org
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 based on those lengths before validating that the compressed data is valid or that the declared expansion is reasonable. A small payload can claim a very large uncompressed length and force a large allocation before LZ4 decoding begins. This vulnerability is fixed in 2.5.301 and 3.1.7.
Affected products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- MessagePack-CSharp · MessagePack-CSharp>= 3.0, < 3.1.7; < 2.5.301
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Unlikely (under 1%). EPSS under 1%, or no score yet.
- CISA KEV
- Not listed
- Public check
- No public nuclei template
- Vendor
- MessagePack-CSharp
- Published
- June 2026
CoverageNo articles yet
No CyberSIXT article names CVE-2026-48510 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.