{"schemaVersion":3,"id":"CVE-2018-4850","aliases":[],"status":"published","duplicateOf":null,"title":null,"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 < 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.","dates":{"published":"2018-05-16T17:00:00.000Z","modified":"2024-09-16T22:46:02.128Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":7.5,"severity":"high","version":"3.0","versionLabel":"v3.0","source":"NVD","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.0","versionLabel":"v3.0","source":"NVD","score":7.5,"severity":"high","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","exploitability":null,"impact":null,"computed":false},{"version":"2.0","versionLabel":"v2.0","source":"NVD","score":5,"severity":"medium","vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.02422,"percentile":0.83947,"severity":"low","asOf":"2026-10-19T00:00:00.000Z","change":{"pp":-0.09000000000000015,"baselineDate":"2026-09-19T00:00:00.000Z","baselineScore":0.02512},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.02512,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.02512,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.02512,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.02512,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.02512,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.02512,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.02512,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.02268,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.02422,"percentile":0.83947}],"last30":[{"date":"2026-09-19T00:00:00.000Z","score":0.02512,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.02512,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.02268,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.02422,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.02422,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Input Validation","description":"The product receives input or data, but it does\n        not validate or incorrectly validates that the input has the\n        properties that are required to process the data safely and\n        correctly.","type":"weakness","status":"Stable","abstraction":"Class","likelihoodOfExploit":"High","url":"https://cwe.mitre.org/data/definitions/20.html"}],"affected":[{"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","name":"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","label":"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","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"SIMATIC S7-400 (incl. F) CPU hardware version 4.0 and below : All versions","noFixRecorded":false,"fixedIn":null},{"text":"SIMATIC S7-400 (incl. F) CPU hardware version 5.0 : All firmware versions < V5.2","noFixRecorded":false,"fixedIn":null},{"text":"SIMATIC S7-400H CPU hardware version 4.5 and below : All versions","noFixRecorded":false,"fixedIn":null}],"versionsText":"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 < V5.2 | SIMATIC S7-400H CPU hardware version 4.5 and below : All versions","eol":null,"hubHref":"/vendor/siemens_ag/simatic_s7-400_incl_f_cpu_hardware_version_40_and_below_simatic_s7-400_incl_f_cpu_hardware_version_50_simatic_s7-400h_cpu_hardware_version_45_and_below"},{"vendor":"siemens","product":"simatic_s7-400_firmware","name":"simatic s7-400 firmware","label":"simatic_s7-400_firmware","ecosystem":null,"cpePart":"o","purl":null,"purlType":null,"versions":[{"text":"≤ 4.0","noFixRecorded":false,"fixedIn":null},{"text":"< 5.2","noFixRecorded":false,"fixedIn":null}],"versionsText":"≤ 4.0 | < 5.2","eol":null,"hubHref":"/vendor/siemens/simatic_s7-400"},{"vendor":"siemens","product":"simatic_s7-400h_firmware","name":"simatic s7-400h firmware","label":"simatic_s7-400h_firmware","ecosystem":null,"cpePart":"o","purl":null,"purlType":null,"versions":[{"text":"≤ 4.5","noFixRecorded":false,"fixedIn":null}],"versionsText":"≤ 4.5","eol":null,"hubHref":"/vendor/siemens/simatic_s7-400h"}],"affectedCount":3,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-914382.pdf","label":"cert-portal.siemens.com/productcert/pdf/ssa-914382.pdf","hostname":"cert-portal.siemens.com","tags":["X Refsource CONFIRM","Vendor Advisory"]},{"url":"http://www.securityfocus.com/bid/104217","label":"www.securityfocus.com/bid/104217","hostname":"www.securityfocus.com","tags":["VDB Entry","X Refsource BID","Third Party Advisory"]},{"url":"https://www.siemens.com/global/en/home/products/services/cert.html#SecurityPublications","label":"www.siemens.com/global/en/home/products/services/cert.html","hostname":"www.siemens.com","tags":["X Refsource CONFIRM","Vendor Advisory"]}],"lineage":{"upstream":[],"downstream":[],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2018-05-16T17:00:00.000Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2024-09-16T22:46:02.128Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":30,"level":"medium","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-19T19:16:42.232Z","stale":false,"partial":false}}