{"id":"CVE-2018-0159","published":"2018-03-28T22:29:00Z","modified":"2026-06-17T01:29:58Z","title":"Cisco IOS and XE Software Internet Key Exchange Version 1 Denial-of-Service Vulnerability","vendor":"Cisco","product":"IOS Software and Cisco IOS XE Software","tier":"core","eol":null,"description":{"text":"A vulnerability in the implementation of Internet Key Exchange Version 1 (IKEv1) functionality in Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability is due to improper validation of specific IKEv1 packets. An attacker could exploit this vulnerability by sending crafted IKEv1 packets to an affected device during an IKE negotiation. A successful exploit could allow the attacker to cause an affected device to reload, resulting in a DoS condition. Cisco Bug IDs: CSCuj73916.","provenance":"source","from":"NVD"},"summary":{"text":"The flaw is improper validation of specific IKEv1 packets in the Internet Key Exchange Version 1 implementation of Cisco IOS Software and Cisco IOS XE Software. An unauthenticated remote attacker can send crafted IKEv1 packets to an affected device during an IKE negotiation, causing the device to reload and resulting in a denial of service.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-23T07:13:44Z"},"cvss":{"score":7.5,"severity":"HIGH","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","provenance":"source","from":"NVD"},"epss":{"score":0.0687,"percentile":0.94031,"date":"2026-10-28","provenance":"source"},"kev":{"dateAdded":"2022-03-03","dueDate":"2022-03-17","ransomware":false,"requiredAction":"Apply updates per vendor instructions.","notes":"https://nvd.nist.gov/vuln/detail/CVE-2018-0159","provenance":"source"},"vulncheckKev":{"dateAdded":"2022-03-03","exploitedFirstSeen":"2022-03-03","ransomware":false,"evidence":[{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2022-03-03"},{"url":"https://www.cisco.com/c/en/us/support/docs/csa/cisco-sa-20180328-ike-dos.html","date":"2022-12-15"}],"evidenceTotal":2,"provenance":"source"},"exploited":true,"otx":{"pulseCount":50,"pulses":[{"name":"Actively_Exploited_Kev | Oct 29, 2026","url":"https://otx.alienvault.com/pulse/6ae20c1db17e7057ae7d9ad1","created":"2026-10-28"},{"name":"Actively_Exploited_Kev | Oct 28, 2026","url":"https://otx.alienvault.com/pulse/6ae0ba7e0e2a97ff7b218819","created":"2026-10-27"},{"name":"Actively_Exploited_Kev | Oct 27, 2026","url":"https://otx.alienvault.com/pulse/6adf68b85c3e852f3c111d18","created":"2026-10-26"},{"name":"Actively_Exploited_Kev | Oct 24, 2026","url":"https://otx.alienvault.com/pulse/6adb740e397c3ad4799aa4cd","created":"2026-10-23"},{"name":"Actively_Exploited_Kev | Oct 23, 2026","url":"https://otx.alienvault.com/pulse/6ada236fcfba2dfa730ea482","created":"2026-10-22"},{"name":"Actively_Exploited_Kev | Oct 22, 2026","url":"https://otx.alienvault.com/pulse/6ad8d33a077cbb5cab524d80","created":"2026-10-21"},{"name":"Actively_Exploited_Kev | Oct 21, 2026","url":"https://otx.alienvault.com/pulse/6ad78130c4d1ac2be83a8b6d","created":"2026-10-20"},{"name":"Actively_Exploited_Kev | Oct 20, 2026","url":"https://otx.alienvault.com/pulse/6ad62f63c24a405a3423cc13","created":"2026-10-19"},{"name":"Actively_Exploited_Kev | Oct 19, 2026","url":"https://otx.alienvault.com/pulse/6ad4dda174e5797d0bd238b7","created":"2026-10-18"},{"name":"Actively_Exploited_Kev | Oct 18, 2026","url":"https://otx.alienvault.com/pulse/6ad38c22e1848f8189d1c121","created":"2026-10-17"}],"provenance":"machine"},"cwes":[{"id":"CWE-20","name":"Improper Input Validation"}],"references":[{"url":"http://www.securityfocus.com/bid/103562","tags":["Broken Link","Third Party Advisory","VDB Entry"]},{"url":"http://www.securitytracker.com/id/1040595","tags":["Broken Link","Third Party Advisory","VDB Entry"]},{"url":"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-ike-dos","tags":["Vendor Advisory"]},{"url":"http://www.securityfocus.com/bid/103562","tags":["Broken Link","Third Party Advisory","VDB Entry"]},{"url":"http://www.securitytracker.com/id/1040595","tags":["Broken Link","Third Party Advisory","VDB Entry"]},{"url":"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-ike-dos","tags":["Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-0159","tags":["US Government Resource"]}],"techniques":[{"id":"T1190","name":"Exploit Public-Facing Application","tactics":["initial-access"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: Crafted packets sent to exposed IKE service","mappingType":"exploitation_technique","evidence":[{"from":"description","quote":"An attacker could exploit this vulnerability by sending crafted IKEv1 packets to an affected device during an IKE negotiation","start":355,"end":480}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"},{"id":"T1499.004","name":"Application or System Exploitation","tactics":["impact"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: Device reload causes application or OS denial of service","mappingType":"primary_impact","evidence":[{"from":"description","quote":"A successful exploit could allow the attacker to cause an affected device to reload, resulting in a DoS condition","start":482,"end":595}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"}],"reports":[],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2018-0982","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2018-0982","exploited":true,"exploitedSince":"2022-03-03","provenance":"source"},"exploits":[],"exploitSources":null,"exploitRefs":[],"flow":[{"stage":"exploitation","techniques":["T1190"],"provenance":"ai"},{"stage":"primary","techniques":["T1499.004"],"provenance":"ai"}],"timeline":[{"date":"2018-03-28","kind":"published","label":"Published (NVD)","url":"https://nvd.nist.gov/vuln/detail/CVE-2018-0159","provenance":"source"},{"date":"2022-03-03","kind":"exploited-reported","label":"Exploitation first reported (VulnCheck KEV evidence)","url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","provenance":"source"},{"date":"2022-03-03","kind":"kev","label":"Added to CISA KEV","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","provenance":"source"},{"date":"2022-03-03","kind":"euvd-exploited","label":"ENISA EUVD: exploited","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2018-0982","provenance":"source"}],"speed":{"daysToPublicExploit":null,"firstExploitFrom":null,"daysToKev":1436},"priority":{"score":62.1,"factors":[{"name":"In a KEV catalog","points":35.0,"detail":"listed in CISA KEV and VulnCheck KEV"},{"name":"Recent KEV listing","points":0.0,"detail":"added 1701 days ago"},{"name":"Known ransomware use","points":0.0,"detail":"not known"},{"name":"EPSS percentile","points":18.81,"detail":"percentile 0.9403"},{"name":"Named in threat reports","points":0.0,"detail":"0 reports"},{"name":"Public exploit code","points":0.0,"detail":"none found"},{"name":"Mentioned in OTX pulses","points":3.0,"detail":"50 pulses"},{"name":"CVSS severity","points":5.25,"detail":"base score 7.5"},{"name":"End-of-life product","points":0.0,"detail":"supported or unknown"}]}}