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 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.
Impacted Technologies
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
< 2.5.301CPE matchmatch criteria | cpe:2.3:a:messagepack:messagepack:*:*:*:*:*:c\#:*:* | ||
>= 3.0.3, < 3.1.7CPE matchmatch criteria | cpe:2.3:a:messagepack:messagepack:*:*:*:*:*:c\#:*:* |
CVSS Data
CVSS version used by this source: 4.0
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Exploit Intelligence
Social Chatter
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Media Mentions
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The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.