{"id":"ALPINE-CVE-2026-92707","details":"MessagePack for C# is a MessagePack serializer for C#. Prior to 2.5.303 and 3.1.9, deserializing attacker-controlled MessagePack data as System.Object through PrimitiveObjectFormatter can cause excessive memory allocation. The formatter allocates an object[] from each declared array length before the configured object-graph depth limit rejects the input, while nested array headers can reuse the same trailing unread bytes to satisfy per-header length validation. A comparatively small payload can therefore keep many large arrays alive at once. When an attacker can submit such data repeatedly, the allocations can cause severe managed-heap pressure, excessive garbage collection, process termination, or loss of service. Exposure requires an application to deserialize untrusted data through the affected formatter path and permit repeated attacker-controlled submissions, such as a reachable ASP.NET Core SignalR hub method with an object parameter and AddMessagePackProtocol() enabled. This issue is fixed in versions 2.5.303 and 3.1.9.","modified":"2026-11-03T06:33:04.592256074Z","published":"2026-10-15T19:17:48.703Z","upstream":["CVE-2026-92707"],"references":[{"type":"ADVISORY","url":"https://security.alpinelinux.org/vuln/CVE-2026-92707"}],"affected":[{"package":{"name":"dotnet10-runtime","ecosystem":"Alpine:v3.23","purl":"pkg:apk/alpine/dotnet10-runtime?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"10.0.13-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2026-92707.json"}},{"package":{"name":"dotnet10-runtime","ecosystem":"Alpine:v3.24","purl":"pkg:apk/alpine/dotnet10-runtime?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"10.0.13-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2026-92707.json"}},{"package":{"name":"dotnet8-runtime","ecosystem":"Alpine:v3.22","purl":"pkg:apk/alpine/dotnet8-runtime?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.0.32-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2026-92707.json"}},{"package":{"name":"dotnet8-runtime","ecosystem":"Alpine:v3.23","purl":"pkg:apk/alpine/dotnet8-runtime?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.0.32-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2026-92707.json"}},{"package":{"name":"dotnet8-runtime","ecosystem":"Alpine:v3.24","purl":"pkg:apk/alpine/dotnet8-runtime?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.0.32-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2026-92707.json"}},{"package":{"name":"dotnet9-runtime","ecosystem":"Alpine:v3.22","purl":"pkg:apk/alpine/dotnet9-runtime?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.0.21-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2026-92707.json"}},{"package":{"name":"dotnet9-runtime","ecosystem":"Alpine:v3.23","purl":"pkg:apk/alpine/dotnet9-runtime?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.0.21-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2026-92707.json"}},{"package":{"name":"dotnet9-runtime","ecosystem":"Alpine:v3.24","purl":"pkg:apk/alpine/dotnet9-runtime?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.0.21-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2026-92707.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"}]}