{"id":"CVE-2024-20406","state":"PUBLISHED","title":"Cisco IOS XR Software Intermediate System-to-Intermediate System Denial of Service Vulnerability","description":"A vulnerability in the segment routing feature for the Intermediate System-to-Intermediate System (IS-IS) protocol of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device.\r\n\r\nThis vulnerability is due to insufficient input validation of ingress IS-IS packets. An attacker could exploit this vulnerability by sending specific IS-IS packets to an affected device after forming an adjacency. A successful exploit could allow the attacker to cause the IS-IS process on all affected devices that are participating in the Flexible Algorithm to crash and restart, resulting in a DoS condition.\r\nNote: The IS-IS protocol is a routing protocol. To exploit this vulnerability, an attacker must be Layer 2-adjacent to the affected device and must have formed an adjacency. This vulnerability affects segment routing for IS-IS over IPv4 and IPv6 control planes as well as devices that are configured as level 1, level 2, or multi-level routing IS-IS type.","publishedAt":"2024-09-11T16:38:50.133Z","updatedAt":"2024-09-11T20:38:41.758Z","severity":{"score":7.4,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","source":"cisco"},"assigner":"cisco","products":["Cisco Cisco IOS XR Software"],"affected":[{"vendor":"Cisco","product":"Cisco IOS XR Software","defaultStatus":"unknown","versions":[{"version":"7.4.1","status":"affected"},{"version":"6.8.1","status":"affected"},{"version":"7.4.15","status":"affected"},{"version":"7.5.1","status":"affected"},{"version":"7.4.16","status":"affected"},{"version":"7.6.1","status":"affected"},{"version":"7.5.2","status":"affected"},{"version":"7.8.1","status":"affected"},{"version":"7.6.15","status":"affected"},{"version":"7.5.12","status":"affected"},{"version":"7.7.1","status":"affected"},{"version":"6.8.2","status":"affected"},{"version":"7.4.2","status":"affected"},{"version":"6.9.1","status":"affected"},{"version":"7.6.2","status":"affected"},{"version":"7.5.3","status":"affected"},{"version":"7.7.2","status":"affected"},{"version":"6.9.2","status":"affected"},{"version":"7.9.1","status":"affected"},{"version":"7.10.1","status":"affected"},{"version":"7.8.2","status":"affected"},{"version":"7.5.4","status":"affected"},{"version":"7.8.22","status":"affected"},{"version":"7.7.21","status":"affected"},{"version":"7.9.2","status":"affected"},{"version":"7.5.5","status":"affected"},{"version":"7.11.1","status":"affected"},{"version":"7.9.21","status":"affected"},{"version":"7.10.2","status":"affected"},{"version":"7.6.3","status":"affected"}]}],"references":["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-isis-xehpbVNe"],"weaknesses":["CWE-20"],"ingestedAt":"2026-10-29T20:06:59.846Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2024/20xxx/CVE-2024-20406.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.1","cveMetadata":{"cveId":"CVE-2024-20406","state":"PUBLISHED","datePublished":"2024-09-11T16:38:50.133Z","dateUpdated":"2024-09-11T20:38:41.758Z","assignerShortName":"cisco","assignerOrgId":"d1c1063e-7a18-46af-9102-31f8928bc633","dateReserved":"2023-11-08T15:08:07.661Z"},"containers":{"cna":{"title":"Cisco IOS XR Software Intermediate System-to-Intermediate System Denial of Service Vulnerability","descriptions":[{"lang":"en","value":"A vulnerability in the segment routing feature for the Intermediate System-to-Intermediate System (IS-IS) protocol of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device.\r\n\r\nThis vulnerability is due to insufficient input validation of ingress IS-IS packets. An attacker could exploit this vulnerability by sending specific IS-IS packets to an affected device after forming an adjacency. A successful exploit could allow the attacker to cause the IS-IS process on all affected devices that are participating in the Flexible Algorithm to crash and restart, resulting in a DoS condition.\r\nNote: The IS-IS protocol is a routing protocol. To exploit this vulnerability, an attacker must be Layer 2-adjacent to the affected device and must have formed an adjacency. This vulnerability affects segment routing for IS-IS over IPv4 and IPv6 control planes as well as devices that are configured as level 1, level 2, or multi-level routing IS-IS type."}],"affected":[{"vendor":"Cisco","product":"Cisco IOS XR Software","defaultStatus":"unknown","versions":[{"version":"7.4.1","status":"affected"},{"version":"6.8.1","status":"affected"},{"version":"7.4.15","status":"affected"},{"version":"7.5.1","status":"affected"},{"version":"7.4.16","status":"affected"},{"version":"7.6.1","status":"affected"},{"version":"7.5.2","status":"affected"},{"version":"7.8.1","status":"affected"},{"version":"7.6.15","status":"affected"},{"version":"7.5.12","status":"affected"},{"version":"7.7.1","status":"affected"},{"version":"6.8.2","status":"affected"},{"version":"7.4.2","status":"affected"},{"version":"6.9.1","status":"affected"},{"version":"7.6.2","status":"affected"},{"version":"7.5.3","status":"affected"},{"version":"7.7.2","status":"affected"},{"version":"6.9.2","status":"affected"},{"version":"7.9.1","status":"affected"},{"version":"7.10.1","status":"affected"},{"version":"7.8.2","status":"affected"},{"version":"7.5.4","status":"affected"},{"version":"7.8.22","status":"affected"},{"version":"7.7.21","status":"affected"},{"version":"7.9.2","status":"affected"},{"version":"7.5.5","status":"affected"},{"version":"7.11.1","status":"affected"},{"version":"7.9.21","status":"affected"},{"version":"7.10.2","status":"affected"},{"version":"7.6.3","status":"affected"}]}],"references":[{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-isis-xehpbVNe","name":"cisco-sa-isis-xehpbVNe"}],"metrics":[{"format":"cvssV3_1","cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","baseScore":7.4,"baseSeverity":"HIGH","attackVector":"ADJACENT_NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-20","lang":"en","description":"Improper Input Validation","type":"cwe"}]}],"providerMetadata":{"shortName":"cisco","orgId":"d1c1063e-7a18-46af-9102-31f8928bc633","dateUpdated":"2024-09-11T16:38:50.133Z"},"exploits":[{"lang":"en","value":"The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory."}],"source":{"advisory":"cisco-sa-isis-xehpbVNe","discovery":"EXTERNAL","defects":["CSCwi39542"]}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2024-09-11T20:38:32.503942Z","id":"CVE-2024-20406","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2024-09-11T20:38:41.758Z"}}]}}}