{"id":"AZL-113012","summary":"CVE-2026-48502 affecting package python-msgpack 1.2.3-1","details":"MessagePack for C# is a MessagePack serializer for C#. Prior to 2.5.301 and 3.1.7, MessagePackReader.ReadDateTime() can allocate stack memory based on an attacker-controlled MessagePack extension length. In the slow path for timestamp extension parsing, the computed tokenSize includes the extension body length from the wire and is used in a stackalloc operation before the extension length is validated as one of the valid timestamp sizes. A very small payload can claim a large timestamp extension body and cause a stack allocation large enough to trigger an uncatchable StackOverflowException, terminating the host process. This vulnerability is fixed in 2.5.301 and 3.1.7.","modified":"2026-11-13T06:04:48Z","published":"2026-06-22T22:16:47Z","upstream":["CVE-2026-48502"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-48502"}],"affected":[{"package":{"name":"python-msgpack","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/python-msgpack"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"1.2.3-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-113012.json"}}],"schema_version":"1.9.2"}