{"id":"CVE-2026-57585","summary":"MessagePack: Out-of-bounds read/crash on Unpacker reuse after caught error","details":"MessagePack is the serializer implementation for Python msgpack.org. Prior to 1.2.1, there is an Out-of-bounds read/crash on Unpacker reuse after a caught error, potentially leading to a DoS attack.  If the Unpacker is used repeatedly after an error occurs, the process may crash with a SEGV. This issue has been fixed in version 1.2.1.","aliases":["GHSA-6v7p-g79w-8964"],"modified":"2026-07-23T19:15:47.789471780Z","published":"2026-06-30T21:36:23.418Z","related":["SUSE-SU-2026:22704-1","SUSE-SU-2026:3113-1","openSUSE-SU-2026:21239-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/57xxx/CVE-2026-57585.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-416"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/57xxx/CVE-2026-57585.json"},{"type":"ADVISORY","url":"https://github.com/msgpack/msgpack-python/security/advisories/GHSA-6v7p-g79w-8964"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-57585"},{"type":"FIX","url":"https://github.com/msgpack/msgpack-python/commit/2c56ddb5d0025ed481d962c0f5d62d19dec7476d"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/msgpack/msgpack-python","events":[{"introduced":"0"},{"fixed":"2c56ddb5d0025ed481d962c0f5d62d19dec7476d"}],"database_specific":{"source":["AFFECTED_FIELD","REFERENCES"],"extracted_events":[{"introduced":"0"},{"fixed":"1.2.1"}]}}],"versions":["v1.2.0","v1.2.0rc1","v1.1.2","v1.1.1","v1.1.1rc1","v1.1.0","v1.1.0rc2","v1.1.0rc1","v1.0.8","v1.0.7","v1.0.6","v1.0.6rc1","v1.0.5","v1.0.5rc1","v1.0.4","v1.0.4rc1","v1.0.3","v1.0.3rc1","v1.0.2","v1.0.1","v1.0.0","v1.0.0rc1","v0.6.2","v0.6.1","v0.6.0","0.5.6","0.5.5","0.5.4","0.5.2","0.5.1","0.5.0","0.4.7","0.4.6","0.4.4","0.4.3","0.4.2","0.4.1","0.4.0","0.3.0","0.2.2","0.2.1","0.2.0","0.1.13","0.1.12","0.1.11","0.1.10"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-57585.json","vanir_signatures_modified":"2026-07-14T20:06:34Z","vanir_signatures":[{"source":"https://github.com/msgpack/msgpack-python/commit/2c56ddb5d0025ed481d962c0f5d62d19dec7476d","target":{"file":"msgpack/unpack_template.h","function":"unpack_construct"},"deprecated":false,"digest":{"function_hash":"172345746607516827835535012763858746409","length":151},"id":"CVE-2026-57585-51ccb1f0","signature_type":"Function","signature_version":"v1"},{"target":{"file":"msgpack/unpack_template.h"},"deprecated":false,"digest":{"threshold":0.9,"line_hashes":["276059310044291053953113173331142530207","47807481533832022339641570168055489655","105278950186171385834643387575749839356","280405200731045814838777584252964803204","104450233282356083671676588003773714637","143910882481720077378192333543456551522","187850785093529631066914756325496747463","100808187545941160794339349893840907724","147870992787760195806441935461531787765","123944175978742985050724227052025282384","181615657339498627546848854308982087142","23650770894844824204353660504341257277","202940592447994686718226457021805112689","316535279066559152719473847323013612945","14343056947174790264509014547871811391","124578409569870610394687527507957586950","237408455507883797531413821133699766908","212366479569126496083887708119009855848","115846675617685161472193634569630554100","271600383821642454526404219558283757510","167540638667161158070463330911310577587","120322024346186537057834128533802367369","285547641352781393631273909925030488973","111374658791803073882630655081927587086","11122174753734765486104659393015209792","313063525532112986523739214669244315316"]},"id":"CVE-2026-57585-63faddfc","signature_type":"Line","signature_version":"v1","source":"https://github.com/msgpack/msgpack-python/commit/2c56ddb5d0025ed481d962c0f5d62d19dec7476d"},{"source":"https://github.com/msgpack/msgpack-python/commit/2c56ddb5d0025ed481d962c0f5d62d19dec7476d","target":{"file":"msgpack/unpack_template.h","function":"unpack_skip"},"deprecated":false,"digest":{"function_hash":"116604020480659683857486196549713437330","length":151},"id":"CVE-2026-57585-68670ebb","signature_type":"Function","signature_version":"v1"},{"signature_version":"v1","source":"https://github.com/msgpack/msgpack-python/commit/2c56ddb5d0025ed481d962c0f5d62d19dec7476d","target":{"file":"msgpack/unpack_template.h","function":"unpack_execute"},"deprecated":false,"digest":{"function_hash":"100436285731131232476092087752718967793","length":6744},"id":"CVE-2026-57585-7355c49f","signature_type":"Function"},{"signature_version":"v1","source":"https://github.com/msgpack/msgpack-python/commit/2c56ddb5d0025ed481d962c0f5d62d19dec7476d","target":{"file":"msgpack/unpack_template.h","function":"unpack_clear"},"deprecated":false,"digest":{"function_hash":"317986275632129119767815112729584778371","length":310},"id":"CVE-2026-57585-9e8aaf65","signature_type":"Function"}]}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}