{"id":"CVE-2018-4850","aliases":["EUVD-2018-16636","GHSA-9c5r-829c-7rjc"],"status":"published","title":"A vulnerability has been identified in SIMATIC S7-400 (incl. F) CPU hardware version 4.0 and...","description":"A vulnerability has been identified in SIMATIC S7-400 (incl. F) CPU hardware version 4.0 and below (All versions), SIMATIC S7-400 (incl. F) CPU hardware version 5.0 (All firmware versions \u003c V5.2), SIMATIC S7-400H CPU hardware version 4.5 and below (All versions). The affected CPUs improperly validate S7 communication packets which could cause a Denial-of-Service condition of the CPU. The CPU will remain in DEFECT mode until manual restart.","severity":{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-08","score":0.02377,"percentile":0.83976,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-20"],"published":"2018-05-16T17:00:00Z","modified":"2026-06-17T01:59:10Z","products":[{"vendor":"siemens","product":"simatic_s7-400_firmware"},{"vendor":"siemens","product":"simatic_s7-400h_firmware"},{"vendor":"siemens ag","product":"simatic s7-400 (incl. f) cpu hardware version 4.0 and below, simatic s7-400 (incl. f) cpu hardware version 5.0, simatic s7-400h cpu hardware version 4.5 and below"}],"references":[{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-914382.pdf","tags":["x_refsource_CONFIRM","x_transferred","Vendor Advisory"]},{"url":"http://www.securityfocus.com/bid/104217","tags":["vdb-entry","x_refsource_BID","x_transferred","Third Party Advisory","VDB Entry"]},{"url":"https://www.siemens.com/global/en/home/products/services/cert.html#SecurityPublications","tags":["x_refsource_CONFIRM","x_transferred","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2018-4850"},{"url":"https://github.com/advisories/GHSA-9c5r-829c-7rjc"}],"sources":{"cve":[{"id":"CVE-2018-4850","description":"A vulnerability has been identified in SIMATIC S7-400 (incl. F) CPU hardware version 4.0 and below (All versions), SIMATIC S7-400 (incl. F) CPU hardware version 5.0 (All firmware versions \u003c V5.2), SIMATIC S7-400H CPU hardware version 4.5 and below (All versions). The affected CPUs improperly validate S7 communication packets which could cause a Denial-of-Service condition of the CPU. The CPU will remain in DEFECT mode until manual restart.","status":"published","published":"2018-05-16T17:00:00Z","modified":"2024-09-16T22:46:02.128Z","cwes":["CWE-20"],"updated_at":"2026-11-02T14:35:08.024147Z"}],"euvd":[{"id":"EUVD-2018-16636","description":"A vulnerability has been identified in SIMATIC S7-400 (incl. F) CPU hardware version 4.0 and below (All versions), SIMATIC S7-400 (incl. F) CPU hardware version 5.0 (All firmware versions \u003c V5.2), SIMATIC S7-400H CPU hardware version 4.5 and below (All versions). The affected CPUs improperly validate S7 communication packets which could cause a Denial-of-Service condition of the CPU. The CPU will remain in DEFECT mode until manual restart.","status":"published","published":"2018-05-16T17:00:00Z","modified":"2024-09-16T22:46:02Z","updated_at":"2026-11-03T00:54:59.7394Z"}],"ghsa":[{"id":"GHSA-9c5r-829c-7rjc","title":"A vulnerability has been identified in SIMATIC S7-400 (incl. F) CPU hardware version 4.0 and...","description":"A vulnerability has been identified in SIMATIC S7-400 (incl. F) CPU hardware version 4.0 and below (All versions), SIMATIC S7-400 (incl. F) CPU hardware version 5.0 (All firmware versions \u003c V5.2), SIMATIC S7-400H CPU hardware version 4.5 and below (All versions). The affected CPUs improperly validate S7 communication packets which could cause a Denial-of-Service condition of the CPU. The CPU will remain in DEFECT mode until manual restart.","status":"published","published":"2022-05-13T01:32:14Z","modified":"2023-02-01T05:08:12Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T14:50:42.317052Z"}],"nvd":[{"id":"CVE-2018-4850","description":"A vulnerability has been identified in SIMATIC S7-400 (incl. F) CPU hardware version 4.0 and below (All versions), SIMATIC S7-400 (incl. F) CPU hardware version 5.0 (All firmware versions \u003c V5.2), SIMATIC S7-400H CPU hardware version 4.5 and below (All versions). The affected CPUs improperly validate S7 communication packets which could cause a Denial-of-Service condition of the CPU. The CPU will remain in DEFECT mode until manual restart.","status":"published","published":"2018-05-16T17:29:00.387Z","modified":"2026-06-17T01:59:10.1Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:04:27.507872Z"}]}}