CVE-2026-48509
Essential information
- Published
- 23/06/2026 00:16
- Modified
- —
- Author
- The MITRE Corporation
- Creator
- The MITRE Corporation
- CVSS
- 9.1 CRITICAL (v3.1) 6.3 MEDIUM (v4.0)
- CISA KEV
- No
- CWE
- CWE-1188
- CVSS vector
-
—
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:HCVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N
CVSS metrics
- Access vector
- —
- Access complexity
- —
- Authentication
- —
- Confidentiality impact
- —
- Integrity impact
- —
- Availability impact
- —
- Exploitability
- —
- Remediation level
- —
- Report confidence
- —
- Temporal score
- —
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- High
- Availability impact
- High
- Exploit code maturity
- —
- Remediation level
- —
- Report confidence
- —
- Temporal score
- —
- Attack vector
- Network
- Attack complexity
- High
- Attack requirements
- Present
- Privileges required
- None
- User interaction
- None
- Confidentiality (V)
- None
- Confidentiality (S)
- None
- Integrity (V)
- Low
- Integrity (S)
- None
- Availability (V)
- Low
- Availability (S)
- None
- Exploit maturity
- —
Description
MessagePack for C# is a MessagePack serializer for C#. Prior to 2.5.301 and 3.1.7, the parameterless MessagePackInputFormatter() constructor uses default serializer options, which resolve to MessagePackSerializerOptions.Standard with MessagePackSecurity.TrustedData. The formatter is designed for ASP.NET Core MVC request bodies, which commonly cross an HTTP trust boundary. This insecure default can expose applications to denial-of-service attacks that MessagePackSecurity.UntrustedData is intended to mitigate, such as hash-collision attacks against dictionary-like model properties. This vulnerability is fixed in 2.5.301 and 3.1.7.
NVD status
- NVD
- View on NVD