CVE-2026-48517 (GCVE-0-2026-48517)
Vulnerability from cvelistv5
Published
2026-06-22 21:03
Modified
2026-06-25 15:55
Severity ?
VLAI Severity ?
EPSS score ?
CWE
Summary
MessagePack for C# is a MessagePack serializer for C#. Prior to 2.5.301 and 3.1.7, MessagePack-CSharp's typeless deserialization includes MessagePackSerializerOptions.ThrowIfDeserializingTypeIsDisallowed(Type) as a safety check for dangerous types. The default implementation checks the outer type name, but it does not recursively inspect array element types or generic type arguments. As a result, a type that would be blocked directly can be wrapped inside an array or constructed generic type and pass the outer type check. The formatter machinery can then materialize formatters for the inner blocked type. This vulnerability is fixed in 2.5.301 and 3.1.7.
References
| URL | Tags | |
|---|---|---|
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| MessagePack-CSharp | MessagePack-CSharp |
Version: >= 3.0, < 3.1.7 Version: < 2.5.301 |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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