{"id":"CVE-2026-66720","aliases":["EUVD-2026-51359","GHSA-r4hv-9qm7-gp9j"],"status":"published","title":"MZ Automation libiec61850 Out-of-bounds Read","description":"The GOOSE subscriber component improperly validates the UTC timestamp \nfield in unauthenticated IEC 61850 GOOSE (EtherType 0x88B8) Layer-2 \nmulticast messages. A specially crafted GOOSE frame containing an \nundersized timestamp field can trigger a heap out-of-bounds read during \nmessage processing, causing the process to crash and resulting in a \ndenial-of-service condition.","severity":{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00285,"percentile":0.21185,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-125"],"published":"2026-07-30T22:46:52Z","modified":"2026-09-03T17:58:18Z","products":[{"vendor":"mz automation","product":"libiec61850"},{"vendor":"mz automation gmbh","product":"libiec61850"}],"references":[{"url":"https://www.cisa.gov/news-events/ics-advisories/icsa-26-211-10"},{"url":"https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-211-10.json"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-66720"},{"url":"https://github.com/advisories/GHSA-r4hv-9qm7-gp9j"}],"sources":{"cve":[{"id":"CVE-2026-66720","title":"MZ Automation libiec61850 Out-of-bounds Read","description":"The GOOSE subscriber component improperly validates the UTC timestamp \nfield in unauthenticated IEC 61850 GOOSE (EtherType 0x88B8) Layer-2 \nmulticast messages. A specially crafted GOOSE frame containing an \nundersized timestamp field can trigger a heap out-of-bounds read during \nmessage processing, causing the process to crash and resulting in a \ndenial-of-service condition.","status":"published","published":"2026-07-30T22:46:52.453Z","modified":"2026-07-31T15:58:46.395Z","cvss":[{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna"}],"cwes":["CWE-125"],"updated_at":"2026-11-02T14:20:12.939084Z"}],"euvd":[{"id":"EUVD-2026-51359","description":"The GOOSE subscriber component improperly validates the UTC timestamp \nfield in unauthenticated IEC 61850 GOOSE (EtherType 0x88B8) Layer-2 \nmulticast messages. A specially crafted GOOSE frame containing an \nundersized timestamp field can trigger a heap out-of-bounds read during \nmessage processing, causing the process to crash and resulting in a \ndenial-of-service condition.","status":"published","published":"2026-07-30T22:46:52Z","modified":"2026-07-31T15:58:46Z","cvss":[{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-02T18:02:25.856077Z"}],"ghsa":[{"id":"GHSA-r4hv-9qm7-gp9j","title":"The GOOSE subscriber component improperly validates the UTC timestamp \nfield in unauthenticated...","description":"The GOOSE subscriber component improperly validates the UTC timestamp \nfield in unauthenticated IEC 61850 GOOSE (EtherType 0x88B8) Layer-2 \nmulticast messages. A specially crafted GOOSE frame containing an \nundersized timestamp field can trigger a heap out-of-bounds read during \nmessage processing, causing the process to crash and resulting in a \ndenial-of-service condition.","status":"published","published":"2026-07-31T00:30:23Z","modified":"2026-07-31T00:30:30Z","cvss":[{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-125"],"updated_at":"2026-11-02T15:09:59.725505Z"}],"nvd":[{"id":"CVE-2026-66720","description":"The GOOSE subscriber component improperly validates the UTC timestamp \nfield in unauthenticated IEC 61850 GOOSE (EtherType 0x88B8) Layer-2 \nmulticast messages. A specially crafted GOOSE frame containing an \nundersized timestamp field can trigger a heap out-of-bounds read during \nmessage processing, causing the process to crash and resulting in a \ndenial-of-service condition.","status":"published","published":"2026-07-30T23:16:53.83Z","modified":"2026-09-03T17:58:18.79Z","cvss":[{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"secondary"}],"cwes":["CWE-125"],"updated_at":"2026-11-02T14:12:33.955581Z"}]}}