{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-20074",
        "assignerOrgId": "d1c1063e-7a18-46af-9102-31f8928bc633",
        "state": "PUBLISHED",
        "assignerShortName": "cisco",
        "dateReserved": "2025-10-08T11:59:15.362Z",
        "datePublished": "2026-03-11T16:31:14.712Z",
        "dateUpdated": "2026-03-11T17:20:21.640Z"
    },
    "containers": {
        "cna": {
            "title": "Cisco IOS XR Software Multi-Instance Intermediate System-to-Intermediate System Denial of Service Vulnerability",
            "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"
                    }
                }
            ],
            "descriptions": [
                {
                    "lang": "en",
                    "value": "A vulnerability in the Intermediate System-to-Intermediate System (IS-IS) multi-instance routing feature of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause the IS-IS process to restart unexpectedly.\r\n\r\nThis vulnerability is due to insufficient input validation of ingress IS-IS packets. An attacker could exploit this vulnerability by sending crafted IS-IS packets to an affected device after forming an adjacency. A successful exploit could allow the attacker to cause the IS-IS process to restart unexpectedly, resulting in a temporary loss of connectivity to advertised networks and a denial of service (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.  "
                }
            ],
            "references": [
                {
                    "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-isis-dos-kDMxpSzK",
                    "name": "cisco-sa-isis-dos-kDMxpSzK"
                }
            ],
            "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-dos-kDMxpSzK",
                "discovery": "INTERNAL",
                "defects": [
                    "CSCwq71827"
                ]
            },
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "description": "Improper Validation of Specified Type of Input",
                            "type": "cwe",
                            "cweId": "CWE-1287"
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "vendor": "Cisco",
                    "product": "Cisco IOS XR Software",
                    "versions": [
                        {
                            "version": "7.8.1",
                            "status": "affected"
                        },
                        {
                            "version": "7.9.1",
                            "status": "affected"
                        },
                        {
                            "version": "7.10.1",
                            "status": "affected"
                        },
                        {
                            "version": "7.8.2",
                            "status": "affected"
                        },
                        {
                            "version": "7.8.22",
                            "status": "affected"
                        },
                        {
                            "version": "7.9.2",
                            "status": "affected"
                        },
                        {
                            "version": "7.11.1",
                            "status": "affected"
                        },
                        {
                            "version": "7.9.21",
                            "status": "affected"
                        },
                        {
                            "version": "7.10.2",
                            "status": "affected"
                        },
                        {
                            "version": "24.1.1",
                            "status": "affected"
                        },
                        {
                            "version": "7.11.2",
                            "status": "affected"
                        },
                        {
                            "version": "24.2.1",
                            "status": "affected"
                        },
                        {
                            "version": "24.1.2",
                            "status": "affected"
                        },
                        {
                            "version": "24.2.11",
                            "status": "affected"
                        },
                        {
                            "version": "24.3.1",
                            "status": "affected"
                        },
                        {
                            "version": "24.4.1",
                            "status": "affected"
                        },
                        {
                            "version": "24.2.2",
                            "status": "affected"
                        },
                        {
                            "version": "7.8.23",
                            "status": "affected"
                        },
                        {
                            "version": "7.11.21",
                            "status": "affected"
                        },
                        {
                            "version": "24.2.20",
                            "status": "affected"
                        },
                        {
                            "version": "24.3.2",
                            "status": "affected"
                        },
                        {
                            "version": "24.4.10",
                            "status": "affected"
                        },
                        {
                            "version": "25.1.1",
                            "status": "affected"
                        },
                        {
                            "version": "24.4.2",
                            "status": "affected"
                        },
                        {
                            "version": "24.3.20",
                            "status": "affected"
                        },
                        {
                            "version": "24.4.15",
                            "status": "affected"
                        },
                        {
                            "version": "25.2.1",
                            "status": "affected"
                        },
                        {
                            "version": "25.1.2",
                            "status": "affected"
                        },
                        {
                            "version": "24.3.30",
                            "status": "affected"
                        },
                        {
                            "version": "24.4.30",
                            "status": "affected"
                        },
                        {
                            "version": "24.2.21",
                            "status": "affected"
                        },
                        {
                            "version": "25.2.15",
                            "status": "affected"
                        }
                    ],
                    "defaultStatus": "unknown"
                }
            ],
            "providerMetadata": {
                "orgId": "d1c1063e-7a18-46af-9102-31f8928bc633",
                "shortName": "cisco",
                "dateUpdated": "2026-03-11T16:31:14.712Z"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "id": "CVE-2026-20074",
                                "role": "CISA Coordinator",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "version": "2.0.3",
                                "timestamp": "2026-03-11T17:04:46.266844Z"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-03-11T17:20:21.640Z"
                }
            }
        ]
    }
}