๐Ÿ” CVE Alert

CVE-2026-48506

HIGH 7.5

MessagePack-CSharp: MessagePackReader.Skip can recurse without enforcing maximum object graph depth

CVSS Score
7.5
EPSS Score
0.0%
EPSS Percentile
0th

MessagePack for C# is a MessagePack serializer for C#. Prior to 2.5.301 and 3.1.7, MessagePackReader.TrySkip() recursively descends into nested arrays and maps without incrementing the reader depth or calling the configured depth checks. This bypasses MessagePackSecurity.MaximumObjectGraphDepth, the library's documented protection against deeply nested object graphs. Many generated and dynamic formatters call reader.Skip() when they encounter unknown map keys, unknown array members, ignored fields, or data that should be skipped for forward compatibility. A deeply nested value in one of these skipped positions can therefore cause unbounded recursion and an uncatchable StackOverflowException. This vulnerability is fixed in 2.5.301 and 3.1.7.

CWE CWE-674
Vendor messagepack-csharp
Product messagepack-csharp
Published Jun 22, 2026
Stay Ahead of the Next One

Get instant alerts for messagepack-csharp messagepack-csharp

Be the first to know when new high vulnerabilities affecting messagepack-csharp messagepack-csharp are published โ€” delivered to Slack, Telegram or Discord.

Get Free Alerts โ†’ Free ยท No credit card ยท 60 sec setup

CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Affected Versions

MessagePack-CSharp / MessagePack-CSharp
>= 3.1.7, < 3.1.7 < 2.5.301

References

NVD โ†— CVE.org โ†— EPSS Data โ†—
github.com: https://github.com/MessagePack-CSharp/MessagePack-CSharp/security/advisories/GHSA-vh6j-jc39-fggf