{"action":"Upgrade MessagePack to 2.5.301 (2.x) or 3.1.7 (3.x) or later.","affected":[{"fixed":"2.5.301","introduced":"0"},{"fixed":"3.1.7","introduced":"3.0.214-rc.1"}],"component":"MessagePack","cve_ids":["CVE-2026-48109"],"ecosystem":"NuGet","epss":0.00509,"exploited":false,"fixed_versions":["2.5.301","3.1.7"],"ghsa_id":"GHSA-hv8m-jj95-wg3x","id":"tcs_01M5N8RD014Y3WNCEKK9KN9ZZK","modified_at":"2026-09-10T03:50:50.662373774Z","published_at":"2026-06-11T20:34:10Z","references":["https://osv.dev/vulnerability/GHSA-hv8m-jj95-wg3x","https://github.com/MessagePack-CSharp/MessagePack-CSharp/security/advisories/GHSA-hv8m-jj95-wg3x","https://nvd.nist.gov/vuln/detail/CVE-2026-48109","https://github.com/MessagePack-CSharp/MessagePack-CSharp"],"severity":{"label":"high","score":8.2},"sources":[{"source":"osv","source_id":"GHSA-hv8m-jj95-wg3x","url":"https://osv.dev/vulnerability/GHSA-hv8m-jj95-wg3x"}],"summary":"MessagePack's LZ4 decompression may fail with AccessViolationException after dereferencing memory from bad input"}