{"id":"CVE-2023-20027","state":"PUBLISHED","title":"Cisco IOS XE Software Virtual Fragmentation Reassembly Denial of Service Vulnerability","description":"A vulnerability in the implementation of the IPv4 Virtual Fragmentation Reassembly (VFR) feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper reassembly of large packets that occurs when VFR is enabled on either a tunnel interface or on a physical interface that is configured with a maximum transmission unit (MTU) greater than 4,615 bytes. An attacker could exploit this vulnerability by sending fragmented packets through a VFR-enabled interface on an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.","publishedAt":"2023-03-23T00:00:00.000Z","updatedAt":"2024-10-28T16:33:06.726Z","severity":{"score":8.6,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","source":"cisco"},"assigner":"cisco","products":["Cisco Cisco IOS XE Software"],"affected":[{"vendor":"Cisco","product":"Cisco IOS XE Software","versions":[{"version":"n/a","status":"affected"}]}],"references":["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ipv4-vfr-dos-CXxtFacb"],"weaknesses":["CWE-416"],"ingestedAt":"2026-10-29T20:05:36.141Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2023/20xxx/CVE-2023-20027.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.1","cveMetadata":{"cveId":"CVE-2023-20027","state":"PUBLISHED","datePublished":"2023-03-23T00:00:00.000Z","dateUpdated":"2024-10-28T16:33:06.726Z","assignerShortName":"cisco","assignerOrgId":"d1c1063e-7a18-46af-9102-31f8928bc633","dateReserved":"2022-10-27T00:00:00.000Z"},"containers":{"cna":{"title":"Cisco IOS XE Software Virtual Fragmentation Reassembly Denial of Service Vulnerability","descriptions":[{"lang":"en","value":"A vulnerability in the implementation of the IPv4 Virtual Fragmentation Reassembly (VFR) feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper reassembly of large packets that occurs when VFR is enabled on either a tunnel interface or on a physical interface that is configured with a maximum transmission unit (MTU) greater than 4,615 bytes. An attacker could exploit this vulnerability by sending fragmented packets through a VFR-enabled interface on an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition."}],"affected":[{"vendor":"Cisco","product":"Cisco IOS XE Software","versions":[{"version":"n/a","status":"affected"}]}],"references":[{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ipv4-vfr-dos-CXxtFacb","name":"20230322 Cisco IOS XE Software Virtual Fragmentation Reassembly Denial of Service Vulnerability","tags":["vendor-advisory"]}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH","baseScore":8.6,"baseSeverity":"HIGH"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-416","type":"CWE","lang":"en","description":"CWE-416"}]}],"providerMetadata":{"shortName":"cisco","orgId":"d1c1063e-7a18-46af-9102-31f8928bc633","dateUpdated":"2023-03-23T00:00:00.000Z"},"datePublic":"2023-03-22T00:00:00.000Z","source":{"advisory":"cisco-sa-ipv4-vfr-dos-CXxtFacb","defect":[["CSCwb45422"]],"discovery":"INTERNAL"},"exploits":[{"lang":"en","value":"The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory."}]},"adp":[{"title":"CVE Program Container","references":[{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ipv4-vfr-dos-CXxtFacb","name":"20230322 Cisco IOS XE Software Virtual Fragmentation Reassembly Denial of Service Vulnerability","tags":["vendor-advisory","x_transferred"]}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2024-08-02T08:57:35.874Z"}},{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2024-10-28T16:24:39.825186Z","id":"CVE-2023-20027","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2024-10-28T16:33:06.726Z"}}]}}}