Microsoft.AspNetCore.SignalR.Protocols.MessagePack: Microsoft Security Advisory CVE-2026-92707 - ASP.NET Core Denial of Service Vulnerability
Description
A denial of service vulnerability exists in Microsoft.AspNetCore.SignalR.Protocols.MessagePack where the MessagePack protocol can consume excessive memory when deserializing deeply nested attacker-controlled arrays. This vulnerability affects multiple versions of the package across Windows, Linux, and macOS platforms. The issue is identified as CWE-1325 and has a CVSS 3.1 score of 5.3 (medium severity). Patched versions have been released to address this vulnerability.
CVSS v3.1
Score 5.3medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Microsoft.AspNetCore.SignalR.Protocols.MessagePack contains a vulnerability that allows unauthenticated remote denial of service due to excessive memory consumption during deserialization of deeply nested arrays controlled by an attacker. This improper memory allocation is tracked as CWE-1325. The vulnerability affects multiple versions of the package, specifically versions >=8.0.0 <8.0.32, >=9.0.0 <9.0.21, >=10.0.0 <10.0.13, and >=11.0.0-preview.5 <11.0.0-rc.2. Microsoft has released patched versions to mitigate this issue.
Potential Impact
The vulnerability can cause denial of service by exhausting memory resources on affected systems when processing maliciously crafted MessagePack data. There is no impact on confidentiality or integrity, only availability is affected. The vulnerability is exploitable remotely without authentication.
Mitigation Recommendations
A fix is available. Users should update to the patched versions of Microsoft.AspNetCore.SignalR.Protocols.MessagePack: 8.0.32, 9.0.21, 10.0.13, or 11.0.0-rc.2 as applicable. Developers should update their .NET SDKs and runtimes accordingly and recompile and redeploy any self-contained applications targeting affected versions. Restart applications after applying updates to ensure the fix takes effect.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-86xp-94pg-8r6r
- Osv Schema Version
- 1.4.0
- Ecosystems
- ["NuGet"]
- Database Specific Severity
- MODERATE
- Cvss Version
- 3.1
Threat ID: 6acea90b2cdf04f656b660a1
Added to database: 10/13/2026, 21:56:27 UTC
Last enriched: 10/13/2026, 21:59:43 UTC
Last updated: 10/13/2026, 21:59:43 UTC
Views: 3
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