{
  "document": {
    "acknowledgments": [
      {
        "summary": "This vulnerability was found during the resolution of a Cisco TAC support case."
      }
    ],
    "category": "csaf_security_advisory",
    "csaf_version": "2.0",
    "notes": [
      {
        "category": "summary",
        "text": "A vulnerability in the IP Version 4 (IPv4) processing code of Cisco IOS XE Software running on Cisco Catalyst 3850 and Cisco Catalyst 3650 Series Switches could allow an unauthenticated, remote attacker to cause high CPU utilization, traceback messages, or a reload of an affected device that leads to a denial of service (DoS) condition.\r\n\r\nThe vulnerability is due to incorrect processing of certain IPv4 packets. An attacker could exploit this vulnerability by sending specific IPv4 packets to an IPv4 address on an affected device. A successful exploit could allow the attacker to cause high CPU utilization, traceback messages, or a reload of the affected device that leads to a DoS condition. If the switch does not reboot when under attack, it would require manual intervention to reload the device.\r\n\r\nCisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.\r\n\r\nThis advisory is available at the following link:\r\nhttps://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-ipv4 [\"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-ipv4\"]\r\nThis advisory is part of the March 28, 2018, release of the Cisco IOS and IOS XE Software Security Advisory Bundled Publication, which includes 20 Cisco Security Advisories that describe 22 vulnerabilities. For a complete list of the advisories and links to them, see Cisco Event Response: March 2018 Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled Publication [\"https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-66682\"].",
        "title": "Summary"
      },
      {
        "category": "general",
        "text": "This vulnerability affects Cisco Catalyst 3850 and Cisco Catalyst 3650 Series Switches that are running Cisco IOS XE Software Release 16.1.1 or later, until the first fixed release, and are configured with an IPv4 address.\r\n\r\nFor more information about which Cisco IOS XE Software releases are vulnerable, see the Fixed Software [\"#fixed\"] section of this advisory.\r\n  Determining the Cisco IOS XE Software Release\r\nTo determine which Cisco IOS XE Software release is running on a device, administrators can log in to the device, use the show version command in the CLI, and then refer to the system banner that appears. If the device is running Cisco IOS XE Software, the system banner displays Cisco IOS Software, Cisco IOS XE Software, or similar text.\r\n\r\nThe following example shows the output of the command for a device that is running Cisco IOS XE Software Release 16.2.1 and has an installed image name of CAT3K_CAA-UNIVERSALK9-M:\r\n\r\n\r\nios-xe-device# show version\r\n  Cisco IOS Software, Catalyst L3 Switch Software (CAT3K_CAA-UNIVERSALK9-M), Version Denali 16.2.1, RELEASE SOFTWARE (fc1)  Technical Support: http://www.cisco.com/techsupport  Copyright (c) 1986-2016 by Cisco Systems, Inc.  Compiled Sun 27-Mar-16 21:47 by mcpre  .  .  .\r\n\r\nFor information about the naming and numbering conventions for Cisco IOS XE Software releases, see the Cisco IOS and NX-OS Software Reference Guide [\"https://www.cisco.com/c/en/us/about/security-center/ios-nx-os-reference-guide.html\"].",
        "title": "Vulnerable Products"
      },
      {
        "category": "general",
        "text": "No other Cisco products are currently known to be affected by this vulnerability.\r\n\r\nCisco has confirmed that this vulnerability does not affect Cisco IOS Software, Cisco IOS XR Software, or Cisco NX-OS Software.",
        "title": "Products Confirmed Not Vulnerable"
      },
      {
        "category": "general",
        "text": "This vulnerability is triggered by certain IPv4 packets that are sent to an affected device. The same IPv4 packets that are sent through the device do not trigger this vulnerability.",
        "title": "Details"
      },
      {
        "category": "general",
        "text": "If an exploit has occurred, the device CPU usage will be high, as shown by the show process cpu sorted CLI command. Depending on the CPU usage, this information may be available only from a console connection, as remote VTY sessions may not be possible. Specifically, the IOSXE-RP Punt Se process will be the one that is consuming the CPU, as shown in the following example:\r\n\r\n\r\nCat3850# show process cpu sorted | ex 0.00\r\n  CPU utilization for five seconds: 96%/66%; one minute: 61%; five minutes: 20%   PID Runtime(ms)     Invoked      uSecs   5Sec   1Min   5Min TTY Process    117       21796       90021        242 40.19% 21.51%  6.27%   0 IOSXE-RP Punt Se   203         153        6311         24  0.07%  0.04%  0.02%   0 IP ARP Retry Age     73        3448        1141       3021  0.07%  0.24%  0.55%   0 IOSD ipc task       200         174        6311         27  0.07%  0.05%  0.04%   0 IPAM Manager       Cat3850#",
        "title": "Indicators of Compromise"
      },
      {
        "category": "general",
        "text": "There are no workarounds that address this vulnerability.\r\n\r\nIf the device has high CPU usage for the IOSXE-RP Punt Se process, try to identify the source of the IP traffic and prevent that address from sending the packets to the affected device, by either filtering the source address or removing the source device from the network.\r\n\r\nTo recover the device, shut down the interface that the IPv4 packets are being received on, eliminate the source of the attack via an infrastructure access control list or other methods, and re-enable the interface.",
        "title": "Workarounds"
      },
      {
        "category": "general",
        "text": "Cisco has released free software updates that address the vulnerability described in this advisory. Customers may only install and expect support for software versions and feature sets for which they have purchased a license. By installing, downloading, accessing, or otherwise using such software upgrades, customers agree to follow the terms of the Cisco software license:\r\nhttps://www.cisco.com/c/en/us/products/end-user-license-agreement.html [\"https://www.cisco.com/c/en/us/products/end-user-license-agreement.html\"]\r\n\r\nAdditionally, customers may only download software for which they have a valid license, procured from Cisco directly, or through a Cisco authorized reseller or partner. In most cases this will be a maintenance upgrade to software that was previously purchased. Free security software updates do not entitle customers to a new software license, additional software feature sets, or major revision upgrades.\r\n\r\nWhen considering software upgrades, customers are advised to regularly consult the advisories for Cisco products, which are available from the Cisco Security Advisories and Alerts page [\"https://www.cisco.com/go/psirt\"], to determine exposure and a complete upgrade solution.\r\n\r\nIn all cases, customers should ensure that the devices to be upgraded contain sufficient memory and confirm that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, customers are advised to contact the Cisco Technical Assistance Center (TAC) or their contracted maintenance providers.\r\n\r\nCustomers Without Service Contracts\r\n\r\nCustomers who purchase directly from Cisco but do not hold a Cisco service contract and customers who make purchases through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should obtain upgrades by contacting the Cisco TAC:\r\nhttps://www.cisco.com/c/en/us/support/web/tsd-cisco-worldwide-contacts.html [\"https://www.cisco.com/c/en/us/support/web/tsd-cisco-worldwide-contacts.html\"]\r\n\r\nCustomers should have the product serial number available and be prepared to provide the URL of this advisory as evidence of entitlement to a free upgrade.\r\n  Fixed Releases\r\nThis vulnerability is fixed in Cisco IOS XE Software Releases Denali 16.3.4, Everest 16.5.1a, Everest 16.5.2, Everest 16.6.1, and later.\r\n                        Cisco IOS and IOS XE Software\r\nTo help customers determine their exposure to vulnerabilities in Cisco IOS and IOS XE Software, Cisco provides a tool, the Cisco IOS Software Checker [\"https://sec.cloudapps.cisco.com/security/center/softwarechecker.x\"], that identifies any Cisco Security Advisories that impact a specific software release and the earliest release that fixes the vulnerabilities described in each advisory (\u201cFirst Fixed\u201d). If applicable, the tool also returns the earliest release that fixes all the vulnerabilities described in all the advisories identified (\u201cCombined First Fixed\u201d).\r\n\r\nCustomers can use this tool to perform the following tasks:\r\n\r\nInitiate a search by choosing one or more releases from a drop-down list or uploading a file from a local system for the tool to parse\r\nEnter the output of the show version command for the tool to parse\r\nCreate a custom search by including all previously published Cisco Security Advisories, a specific advisory, or all advisories in the most recent bundled publication\r\n\r\nTo determine whether a release is affected by any published Cisco Security Advisory, use the Cisco IOS Software Checker [\"https://sec.cloudapps.cisco.com/security/center/softwarechecker.x\"] on Cisco.com or enter a Cisco IOS Software or Cisco IOS XE Software release\u2014for example, 15.1(4)M2 or 3.13.8S\u2014in the following field:\r\n\r\n\r\n\r\n\r\n\r\nFor a mapping of Cisco IOS XE Software releases to Cisco IOS Software releases, refer to the Cisco IOS XE 2 Release Notes [\"https://www.cisco.com/c/en/us/td/docs/ios/ios_xe/2/release/notes/rnasr21/rnasr21_gen.html#wp3000032\"], Cisco IOS XE 3S Release Notes [\"https://www.cisco.com/c/en/us/td/docs/ios/ios_xe/3/release/notes/asr1k_rn_3s_rel_notes/asr1k_rn_3s_sys_req.html#wp3069754\"], or Cisco IOS XE 3SG Release Notes [\"https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/release/note/OL_24726.html#pgfId-2570252\"], depending on the Cisco IOS XE Software release.",
        "title": "Fixed Software"
      },
      {
        "category": "general",
        "text": "To learn about Cisco security vulnerability disclosure policies and publications, see the Security Vulnerability Policy [\"https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html\"]. This document also contains instructions for obtaining fixed software and receiving security vulnerability information from Cisco.",
        "title": "Vulnerability Policy"
      },
      {
        "category": "general",
        "text": "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.",
        "title": "Exploitation and Public Announcements"
      },
      {
        "category": "general",
        "text": "This vulnerability was found during the resolution of a Cisco TAC support case.",
        "title": "Source"
      },
      {
        "category": "legal_disclaimer",
        "text": "THIS DOCUMENT IS PROVIDED ON AN \"AS IS\" BASIS AND DOES NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE INFORMATION ON THE DOCUMENT OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME.\r\n\r\nA standalone copy or paraphrase of the text of this document that omits the distribution URL is an uncontrolled copy and may lack important information or contain factual errors. The information in this document is intended for end users of Cisco products.",
        "title": "Legal Disclaimer"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "Emergency Support:\r\n+1 877 228 7302 (toll-free within North America)\r\n+1 408 525 6532 (International direct-dial)\r\nNon-emergency Support:\r\nEmail: psirt@cisco.com\r\nSupport requests that are received via e-mail are typically acknowledged within 48 hours.",
      "issuing_authority": "Cisco product security incident response is the responsibility of the Cisco Product Security Incident Response Team (PSIRT). The Cisco PSIRT is a dedicated, global team that manages the receipt, investigation, and public reporting of security vulnerability information that is related to Cisco products and networks. The on-call Cisco PSIRT works 24x7 with Cisco customers, independent security researchers, consultants, industry organizations, and other vendors to identify possible security issues with Cisco products and networks.\r\nMore information can be found in Cisco Security Vulnerability Policy available at https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html",
      "name": "Cisco",
      "namespace": "https://wwww.cisco.com"
    },
    "references": [
      {
        "category": "self",
        "summary": "Cisco IOS XE Software for Cisco Catalyst Switches IPv4 Denial of Service Vulnerability",
        "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-ipv4"
      },
      {
        "category": "external",
        "summary": "Cisco Event Response: March 2018 Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled Publication",
        "url": "https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-66682"
      },
      {
        "category": "external",
        "summary": "Cisco Security Vulnerability Policy",
        "url": "https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html"
      },
      {
        "category": "external",
        "summary": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-ipv4",
        "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-ipv4"
      },
      {
        "category": "external",
        "summary": "Cisco Event Response: March 2018 Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled Publication",
        "url": "https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-66682"
      },
      {
        "category": "external",
        "summary": "Cisco IOS and NX-OS Software Reference Guide",
        "url": "https://www.cisco.com/c/en/us/about/security-center/ios-nx-os-reference-guide.html"
      },
      {
        "category": "external",
        "summary": "https://www.cisco.com/c/en/us/products/end-user-license-agreement.html",
        "url": "https://www.cisco.com/c/en/us/products/end-user-license-agreement.html"
      },
      {
        "category": "external",
        "summary": "Cisco Security Advisories and Alerts page",
        "url": "https://www.cisco.com/go/psirt"
      },
      {
        "category": "external",
        "summary": "https://www.cisco.com/c/en/us/support/web/tsd-cisco-worldwide-contacts.html",
        "url": "https://www.cisco.com/c/en/us/support/web/tsd-cisco-worldwide-contacts.html"
      },
      {
        "category": "external",
        "summary": "Cisco\u0026nbsp;IOS Software Checker",
        "url": "https://sec.cloudapps.cisco.com/security/center/softwarechecker.x"
      },
      {
        "category": "external",
        "summary": "Cisco\u0026nbsp;IOS Software Checker",
        "url": "https://sec.cloudapps.cisco.com/security/center/softwarechecker.x"
      },
      {
        "category": "external",
        "summary": "Cisco\u0026nbsp;IOS XE 2 Release Notes",
        "url": "https://www.cisco.com/c/en/us/td/docs/ios/ios_xe/2/release/notes/rnasr21/rnasr21_gen.html#wp3000032"
      },
      {
        "category": "external",
        "summary": "Cisco\u0026nbsp;IOS XE 3S Release Notes",
        "url": "https://www.cisco.com/c/en/us/td/docs/ios/ios_xe/3/release/notes/asr1k_rn_3s_rel_notes/asr1k_rn_3s_sys_req.html#wp3069754"
      },
      {
        "category": "external",
        "summary": "Cisco\u0026nbsp;IOS XE 3SG Release Notes",
        "url": "https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/release/note/OL_24726.html#pgfId-2570252"
      },
      {
        "category": "external",
        "summary": "Security Vulnerability Policy",
        "url": "https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html"
      }
    ],
    "title": "Cisco IOS XE Software for Cisco Catalyst Switches IPv4 Denial of Service Vulnerability",
    "tracking": {
      "current_release_date": "2018-03-28T16:00:00+00:00",
      "generator": {
        "date": "2022-09-03T03:01:00+00:00",
        "engine": {
          "name": "TVCE"
        }
      },
      "id": "cisco-sa-20180328-ipv4",
      "initial_release_date": "2018-03-28T16:00:00+00:00",
      "revision_history": [
        {
          "date": "2018-03-28T15:12:15+00:00",
          "number": "1.0.0",
          "summary": "Initial public release."
        }
      ],
      "status": "final",
      "version": "1.0.0"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "branches": [
                  {
                    "category": "service_pack",
                    "name": "16.1.1",
                    "product": {
                      "name": "16.1.1",
                      "product_id": "CSAFPID-212436"
                    }
                  },
                  {
                    "category": "service_pack",
                    "name": "16.1.2",
                    "product": {
                      "name": "16.1.2",
                      "product_id": "CSAFPID-213100"
                    }
                  },
                  {
                    "category": "service_pack",
                    "name": "16.1.3",
                    "product": {
                      "name": "16.1.3",
                      "product_id": "CSAFPID-214993"
                    }
                  }
                ],
                "category": "product_version",
                "name": "16.1"
              },
              {
                "branches": [
                  {
                    "category": "service_pack",
                    "name": "16.2.1",
                    "product": {
                      "name": "16.2.1",
                      "product_id": "CSAFPID-213809"
                    }
                  },
                  {
                    "category": "service_pack",
                    "name": "16.2.2",
                    "product": {
                      "name": "16.2.2",
                      "product_id": "CSAFPID-217253"
                    }
                  }
                ],
                "category": "product_version",
                "name": "16.2"
              },
              {
                "branches": [
                  {
                    "category": "service_pack",
                    "name": "16.3.1",
                    "product": {
                      "name": "16.3.1",
                      "product_id": "CSAFPID-213960"
                    }
                  },
                  {
                    "category": "service_pack",
                    "name": "16.3.2",
                    "product": {
                      "name": "16.3.2",
                      "product_id": "CSAFPID-217255"
                    }
                  },
                  {
                    "category": "service_pack",
                    "name": "16.3.3",
                    "product": {
                      "name": "16.3.3",
                      "product_id": "CSAFPID-217256"
                    }
                  },
                  {
                    "category": "service_pack",
                    "name": "16.3.1a",
                    "product": {
                      "name": "16.3.1a",
                      "product_id": "CSAFPID-220802"
                    }
                  }
                ],
                "category": "product_version",
                "name": "16.3"
              },
              {
                "branches": [
                  {
                    "category": "service_pack",
                    "name": "16.4.1",
                    "product": {
                      "name": "16.4.1",
                      "product_id": "CSAFPID-214051"
                    }
                  },
                  {
                    "category": "service_pack",
                    "name": "16.4.2",
                    "product": {
                      "name": "16.4.2",
                      "product_id": "CSAFPID-217257"
                    }
                  },
                  {
                    "category": "service_pack",
                    "name": "16.4.3",
                    "product": {
                      "name": "16.4.3",
                      "product_id": "CSAFPID-231390"
                    }
                  }
                ],
                "category": "product_version",
                "name": "16.4"
              },
              {
                "branches": [
                  {
                    "category": "service_pack",
                    "name": "16.5.1",
                    "product": {
                      "name": "16.5.1",
                      "product_id": "CSAFPID-217259"
                    }
                  },
                  {
                    "category": "service_pack",
                    "name": "16.5.1b",
                    "product": {
                      "name": "16.5.1b",
                      "product_id": "CSAFPID-226330"
                    }
                  }
                ],
                "category": "product_version",
                "name": "16.5"
              }
            ],
            "category": "product_family",
            "name": "Cisco IOS XE Software"
          }
        ],
        "category": "vendor",
        "name": "Cisco"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2018-0177",
      "ids": [
        {
          "system_name": "Cisco Bug ID",
          "text": "CSCvd80714"
        }
      ],
      "notes": [
        {
          "category": "other",
          "text": "Complete.",
          "title": "Affected Product Comprehensiveness"
        }
      ],
      "product_status": {
        "known_affected": [
          "CSAFPID-212436",
          "CSAFPID-213100",
          "CSAFPID-213809",
          "CSAFPID-213960",
          "CSAFPID-214051",
          "CSAFPID-214993",
          "CSAFPID-217253",
          "CSAFPID-217255",
          "CSAFPID-217256",
          "CSAFPID-217257",
          "CSAFPID-217259",
          "CSAFPID-220802",
          "CSAFPID-226330",
          "CSAFPID-231390"
        ]
      },
      "release_date": "2018-03-28T16:00:00+00:00",
      "remediations": [
        {
          "category": "vendor_fix",
          "details": "Cisco has released software updates that address this vulnerability.",
          "product_ids": [
            "CSAFPID-212436",
            "CSAFPID-213100",
            "CSAFPID-213809",
            "CSAFPID-213960",
            "CSAFPID-214051",
            "CSAFPID-214993",
            "CSAFPID-217253",
            "CSAFPID-217255",
            "CSAFPID-217256",
            "CSAFPID-217257",
            "CSAFPID-217259",
            "CSAFPID-220802",
            "CSAFPID-226330",
            "CSAFPID-231390"
          ],
          "url": "https://software.cisco.com"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 8.6,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H",
            "version": "3.0"
          },
          "products": [
            "CSAFPID-212436",
            "CSAFPID-213100",
            "CSAFPID-213809",
            "CSAFPID-213960",
            "CSAFPID-214051",
            "CSAFPID-214993",
            "CSAFPID-217253",
            "CSAFPID-217255",
            "CSAFPID-217256",
            "CSAFPID-217257",
            "CSAFPID-217259",
            "CSAFPID-220802",
            "CSAFPID-226330",
            "CSAFPID-231390"
          ]
        }
      ],
      "title": "Cisco IOS XE Software for Cisco Catalyst Switches IPv4 Denial of Service Vulnerability"
    }
  ]
}