{"items":[{"id":"NVI-00018590","kind":"vulnerability","title":"Microsoft Security Advisory CVE-2026-45591 – ASP.NET Core Denial of Service Vulnerability","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-f8h2-vmm9-qhj6","CVE-2026-45591"],"plain_summary":"GitHub lists this reviewed advisory for Microsoft.AspNetCore.App.Runtime.linux-x64, Microsoft.AspNetCore.App.Runtime.linux-x64, Microsoft.AspNetCore.App.Runtime.linux-x64, Microsoft.AspNetCore.App.Runtime.win-x64, Microsoft.AspNetCore.App.Runtime.win-x64. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-41166d38d79cad8517b074fce07b5a7e"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-06-15T20:11:57.000Z","value":"7.5 high","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-41166d38d79cad8517b074fce07b5a7e"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-41166d38d79cad8517b074fce07b5a7e","url":"https://github.com/advisories/GHSA-f8h2-vmm9-qhj6","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-f8h2-vmm9-qhj6","publisher":"GitHub Advisory Database","observed_at":"2026-11-06T07:20:20.042Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-41166d38d79cad8517b074fce07b5a7e"],"technology":"Microsoft.AspNetCore.App.Runtime.linux-x64","known_exclusions":[],"conditions_summary":"## Executive summary\n\nMicrosoft is releasing this security advisory to provide information about a vulnerability in ASP.NET Core SignalR and Blazor Server. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.\n\nA denial of service vulnerability exists in the MessagePack hub protocol used by SignalR and Blazor Server where an attacker can send deeply-nested MessagePack arrays to cause a stack overflow, resulting in a denial of service.\n\n## Announcement\n\nAnnouncement for this issue can be found at https://github.com/dotnet/announcements/issues/405\n\n## Affected Platforms\n\n- **Platforms:** All\n- **Architectures:** All\n\n## Affected Packages\nThe vulnerability affects any Microsoft .NET project if it uses any of affected package versions listed below\n\n### .NET 10\nPackage name | Affected version | Patched version\n------------ | ---------------- | -------------------------\nMicrosoft.AspNetCore.App.Runtime.linux-arm               | >= 10.0.0, <= 10.0.8 | 10.0.9\n[Microsoft.AspNetCore.App.Runtime.l","public_affected_ranges":[">= 8.0.0, <= 8.0.27"]},{"certainty":"source_listed","source_ids":["sr-41166d38d79cad8517b074fce07b5a7e"],"technology":"Microsoft.AspNetCore.App.Runtime.linux-x64","known_exclusions":[],"conditions_summary":"## Executive summary\n\nMicrosoft is releasing this security advisory to provide information about a vulnerability in ASP.NET Core SignalR and Blazor Server. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.\n\nA denial of service vulnerability exists in the MessagePack hub protocol used by SignalR and Blazor Server where an attacker can send deeply-nested MessagePack arrays to cause a stack overflow, resulting in a denial of service.\n\n## Announcement\n\nAnnouncement for this issue can be found at https://github.com/dotnet/announcements/issues/405\n\n## Affected Platforms\n\n- **Platforms:** All\n- **Architectures:** All\n\n## Affected Packages\nThe vulnerability affects any Microsoft .NET project if it uses any of affected package versions listed below\n\n### .NET 10\nPackage name | Affected version | Patched version\n------------ | ---------------- | -------------------------\nMicrosoft.AspNetCore.App.Runtime.linux-arm               | >= 10.0.0, <= 10.0.8 | 10.0.9\n[Microsoft.AspNetCore.App.Runtime.l","public_affected_ranges":[">= 9.0.0, <= 9.0.16"]},{"certainty":"source_listed","source_ids":["sr-41166d38d79cad8517b074fce07b5a7e"],"technology":"Microsoft.AspNetCore.App.Runtime.linux-x64","known_exclusions":[],"conditions_summary":"## Executive summary\n\nMicrosoft is releasing this security advisory to provide information about a vulnerability in ASP.NET Core SignalR and Blazor Server. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.\n\nA denial of service vulnerability exists in the MessagePack hub protocol used by SignalR and Blazor Server where an attacker can send deeply-nested MessagePack arrays to cause a stack overflow, resulting in a denial of service.\n\n## Announcement\n\nAnnouncement for this issue can be found at https://github.com/dotnet/announcements/issues/405\n\n## Affected Platforms\n\n- **Platforms:** All\n- **Architectures:** All\n\n## Affected Packages\nThe vulnerability affects any Microsoft .NET project if it uses any of affected package versions listed below\n\n### .NET 10\nPackage name | Affected version | Patched version\n------------ | ---------------- | -------------------------\nMicrosoft.AspNetCore.App.Runtime.linux-arm               | >= 10.0.0, <= 10.0.8 | 10.0.9\n[Microsoft.AspNetCore.App.Runtime.l","public_affected_ranges":[">= 10.0.0, <= 10.0.8"]},{"certainty":"source_listed","source_ids":["sr-41166d38d79cad8517b074fce07b5a7e"],"technology":"Microsoft.AspNetCore.App.Runtime.win-x64","known_exclusions":[],"conditions_summary":"## Executive summary\n\nMicrosoft is releasing this security advisory to provide information about a vulnerability in ASP.NET Core SignalR and Blazor Server. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.\n\nA denial of service vulnerability exists in the MessagePack hub protocol used by SignalR and Blazor Server where an attacker can send deeply-nested MessagePack arrays to cause a stack overflow, resulting in a denial of service.\n\n## Announcement\n\nAnnouncement for this issue can be found at https://github.com/dotnet/announcements/issues/405\n\n## Affected Platforms\n\n- **Platforms:** All\n- **Architectures:** All\n\n## Affected Packages\nThe vulnerability affects any Microsoft .NET project if it uses any of affected package versions listed below\n\n### .NET 10\nPackage name | Affected version | Patched version\n------------ | ---------------- | -------------------------\nMicrosoft.AspNetCore.App.Runtime.linux-arm               | >= 10.0.0, <= 10.0.8 | 10.0.9\n[Microsoft.AspNetCore.App.Runtime.l","public_affected_ranges":[">= 8.0.0, <= 8.0.27"]},{"certainty":"source_listed","source_ids":["sr-41166d38d79cad8517b074fce07b5a7e"],"technology":"Microsoft.AspNetCore.App.Runtime.win-x64","known_exclusions":[],"conditions_summary":"## Executive summary\n\nMicrosoft is releasing this security advisory to provide information about a vulnerability in ASP.NET Core SignalR and Blazor Server. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.\n\nA denial of service vulnerability exists in the MessagePack hub protocol used by SignalR and Blazor Server where an attacker can send deeply-nested MessagePack arrays to cause a stack overflow, resulting in a denial of service.\n\n## Announcement\n\nAnnouncement for this issue can be found at https://github.com/dotnet/announcements/issues/405\n\n## Affected Platforms\n\n- **Platforms:** All\n- **Architectures:** All\n\n## Affected Packages\nThe vulnerability affects any Microsoft .NET project if it uses any of affected package versions listed below\n\n### .NET 10\nPackage name | Affected version | Patched version\n------------ | ---------------- | -------------------------\nMicrosoft.AspNetCore.App.Runtime.linux-arm               | >= 10.0.0, <= 10.0.8 | 10.0.9\n[Microsoft.AspNetCore.App.Runtime.l","public_affected_ranges":[">= 9.0.0, <= 9.0.16"]},{"certainty":"source_listed","source_ids":["sr-41166d38d79cad8517b074fce07b5a7e"],"technology":"Microsoft.AspNetCore.App.Runtime.win-x64","known_exclusions":[],"conditions_summary":"## Executive summary\n\nMicrosoft is releasing this security advisory to provide information about a vulnerability in ASP.NET Core SignalR and Blazor Server. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.\n\nA denial of service vulnerability exists in the MessagePack hub protocol used by SignalR and Blazor Server where an attacker can send deeply-nested MessagePack arrays to cause a stack overflow, resulting in a denial of service.\n\n## Announcement\n\nAnnouncement for this issue can be found at https://github.com/dotnet/announcements/issues/405\n\n## Affected Platforms\n\n- **Platforms:** All\n- **Architectures:** All\n\n## Affected Packages\nThe vulnerability affects any Microsoft .NET project if it uses any of affected package versions listed below\n\n### .NET 10\nPackage name | Affected version | Patched version\n------------ | ---------------- | -------------------------\nMicrosoft.AspNetCore.App.Runtime.linux-arm               | >= 10.0.0, <= 10.0.8 | 10.0.9\n[Microsoft.AspNetCore.App.Runtime.l","public_affected_ranges":[">= 10.0.0, <= 10.0.8"]},{"certainty":"source_listed","source_ids":["sr-41166d38d79cad8517b074fce07b5a7e"],"technology":"Microsoft.AspNetCore.App.Runtime.osx-arm64","known_exclusions":[],"conditions_summary":"## Executive summary\n\nMicrosoft is releasing this security advisory to provide information about a vulnerability in ASP.NET Core SignalR and Blazor Server. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.\n\nA denial of service vulnerability exists in the MessagePack hub protocol used by SignalR and Blazor Server where an attacker can send deeply-nested MessagePack arrays to cause a stack overflow, resulting in a denial of service.\n\n## Announcement\n\nAnnouncement for this issue can be found at https://github.com/dotnet/announcements/issues/405\n\n## Affected Platforms\n\n- **Platforms:** All\n- **Architectures:** All\n\n## Affected Packages\nThe vulnerability affects any Microsoft .NET project if it uses any of affected package versions listed below\n\n### .NET 10\nPackage name | Affected version | Patched version\n------------ | ---------------- | -------------------------\nMicrosoft.AspNetCore.App.Runtime.linux-arm               | >= 10.0.0, <= 10.0.8 | 10.0.9\n[Microsoft.AspNetCore.App.Runtime.l","public_affected_ranges":[">= 8.0.0, <= 8.0.27"]},{"certainty":"source_listed","source_ids":["sr-41166d38d79cad8517b074fce07b5a7e"],"technology":"Microsoft.AspNetCore.App.Runtime.osx-arm64","known_exclusions":[],"conditions_summary":"## Executive summary\n\nMicrosoft is releasing this security advisory to provide information about a vulnerability in ASP.NET Core SignalR and Blazor Server. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.\n\nA denial of service vulnerability exists in the MessagePack hub protocol used by SignalR and Blazor Server where an attacker can send deeply-nested MessagePack arrays to cause a stack overflow, resulting in a denial of service.\n\n## Announcement\n\nAnnouncement for this issue can be found at https://github.com/dotnet/announcements/issues/405\n\n## Affected Platforms\n\n- **Platforms:** All\n- **Architectures:** All\n\n## Affected Packages\nThe vulnerability affects any Microsoft .NET project if it uses any of affected package versions listed below\n\n### .NET 10\nPackage name | Affected version | Patched version\n------------ | ---------------- | -------------------------\nMicrosoft.AspNetCore.App.Runtime.linux-arm               | >= 10.0.0, <= 10.0.8 | 10.0.9\n[Microsoft.AspNetCore.App.Runtime.l","public_affected_ranges":[">= 9.0.0, <= 9.0.16"]},{"certainty":"source_listed","source_ids":["sr-41166d38d79cad8517b074fce07b5a7e"],"technology":"Microsoft.AspNetCore.App.Runtime.osx-arm64","known_exclusions":[],"conditions_summary":"## Executive summary\n\nMicrosoft is releasing this security advisory to provide information about a vulnerability in ASP.NET Core SignalR and Blazor Server. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.\n\nA denial of service vulnerability exists in the MessagePack hub protocol used by SignalR and Blazor Server where an attacker can send deeply-nested MessagePack arrays to cause a stack overflow, resulting in a denial of service.\n\n## Announcement\n\nAnnouncement for this issue can be found at https://github.com/dotnet/announcements/issues/405\n\n## Affected Platforms\n\n- **Platforms:** All\n- **Architectures:** All\n\n## Affected Packages\nThe vulnerability affects any Microsoft .NET project if it uses any of affected package versions listed below\n\n### .NET 10\nPackage name | Affected version | Patched version\n------------ | ---------------- | -------------------------\nMicrosoft.AspNetCore.App.Runtime.linux-arm               | >= 10.0.0, <= 10.0.8 | 10.0.9\n[Microsoft.AspNetCore.App.Runtime.l","public_affected_ranges":[">= 10.0.0, <= 10.0.8"]},{"certainty":"source_listed","source_ids":["sr-41166d38d79cad8517b074fce07b5a7e"],"technology":"Microsoft.AspNetCore.SignalR.Protocols.MessagePack","known_exclusions":[],"conditions_summary":"## Executive summary\n\nMicrosoft is releasing this security advisory to provide information about a vulnerability in ASP.NET Core SignalR and Blazor Server. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.\n\nA denial of service vulnerability exists in the MessagePack hub protocol used by SignalR and Blazor Server where an attacker can send deeply-nested MessagePack arrays to cause a stack overflow, resulting in a denial of service.\n\n## Announcement\n\nAnnouncement for this issue can be found at https://github.com/dotnet/announcements/issues/405\n\n## Affected Platforms\n\n- **Platforms:** All\n- **Architectures:** All\n\n## Affected Packages\nThe vulnerability affects any Microsoft .NET project if it uses any of affected package versions listed below\n\n### .NET 10\nPackage name | Affected version | Patched version\n------------ | ---------------- | -------------------------\nMicrosoft.AspNetCore.App.Runtime.linux-arm               | >= 10.0.0, <= 10.0.8 | 10.0.9\n[Microsoft.AspNetCore.App.Runtime.l","public_affected_ranges":[">= 8.0.0, <= 8.0.27"]},{"certainty":"source_listed","source_ids":["sr-41166d38d79cad8517b074fce07b5a7e"],"technology":"Microsoft.AspNetCore.SignalR.Protocols.MessagePack","known_exclusions":[],"conditions_summary":"## Executive summary\n\nMicrosoft is releasing this security advisory to provide information about a vulnerability in ASP.NET Core SignalR and Blazor Server. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.\n\nA denial of service vulnerability exists in the MessagePack hub protocol used by SignalR and Blazor Server where an attacker can send deeply-nested MessagePack arrays to cause a stack overflow, resulting in a denial of service.\n\n## Announcement\n\nAnnouncement for this issue can be found at https://github.com/dotnet/announcements/issues/405\n\n## Affected Platforms\n\n- **Platforms:** All\n- **Architectures:** All\n\n## Affected Packages\nThe vulnerability affects any Microsoft .NET project if it uses any of affected package versions listed below\n\n### .NET 10\nPackage name | Affected version | Patched version\n------------ | ---------------- | -------------------------\nMicrosoft.AspNetCore.App.Runtime.linux-arm               | >= 10.0.0, <= 10.0.8 | 10.0.9\n[Microsoft.AspNetCore.App.Runtime.l","public_affected_ranges":[">= 9.0.0, <= 9.0.16"]},{"certainty":"source_listed","source_ids":["sr-41166d38d79cad8517b074fce07b5a7e"],"technology":"Microsoft.AspNetCore.SignalR.Protocols.MessagePack","known_exclusions":[],"conditions_summary":"## Executive summary\n\nMicrosoft is releasing this security advisory to provide information about a vulnerability in ASP.NET Core SignalR and Blazor Server. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.\n\nA denial of service vulnerability exists in the MessagePack hub protocol used by SignalR and Blazor Server where an attacker can send deeply-nested MessagePack arrays to cause a stack overflow, resulting in a denial of service.\n\n## Announcement\n\nAnnouncement for this issue can be found at https://github.com/dotnet/announcements/issues/405\n\n## Affected Platforms\n\n- **Platforms:** All\n- **Architectures:** All\n\n## Affected Packages\nThe vulnerability affects any Microsoft .NET project if it uses any of affected package versions listed below\n\n### .NET 10\nPackage name | Affected version | Patched version\n------------ | ---------------- | -------------------------\nMicrosoft.AspNetCore.App.Runtime.linux-arm               | >= 10.0.0, <= 10.0.8 | 10.0.9\n[Microsoft.AspNetCore.App.Runtime.l","public_affected_ranges":[">= 10.0.0, <= 10.0.8"]}],"null_published_at":"2026-11-07T07:07:39.859Z","source_updated_at":"2026-06-15T20:11:57.000Z","source_disclosed_at":"2026-06-15T20:11:56.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-11-06T07:20:20.042Z"}],"next_cursor":null,"snapshot_revision":"42594"}