CVE-2026-48513
MEDIUM EPSS 13.9%
Published Jun 22, 20261w ago · Modified Jun 23, 20261w ago
6.3 CVSS 4.0
Published Jun 22, 2026 1w ago
Last Modified Jun 23, 2026 1w ago
Description
MessagePack for C# is a MessagePack serializer for C#. Prior to 2.5.301 and 3.1.7, runtime-generated union deserializers emitted by DynamicUnionResolver do not call MessagePackSecurity.DepthStep(ref reader) and do not decrement reader.Depth around recursive deserialization and skip paths. This means union deserialization does not consistently participate in the maximum object graph depth enforcement that protects other recursive formatter paths. For unknown union keys, the emitted deserializer calls reader.Skip() on attacker-controlled data without an enclosing depth step. This vulnerability is fixed in 2.5.301 and 3.1.7.
CVSS Details
Base Score
Exploitability
Impact
Vector string
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 Attack Vector Network
Attack Complexity High
Privileges Required None
User Interaction None
Scope X
Threat Intelligence
EPSS Exploit Probability
13.9% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 1
CWE-674
Affected Products 2
| Vendor | Product | Version | Range |
|---|---|---|---|
| messagepack | messagepack | * | <2.5.301 |
| messagepack | messagepack | * | ≥3.0.3 – <3.1.7 |
References 1
- github.com https://github.com/MessagePack-CSharp/MessagePack-CSharp/security/advisories/GHSA-wfr3-xj75-pfwh
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.