{
  "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 internal packet processing of Cisco Aironet Series Access Points (APs) could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected AP if the switch interface where the AP is connected has port security configured.\r\n\r\nThe vulnerability exists because the AP forwards some malformed wireless client packets outside of the Control and Provisioning of Wireless Access Points (CAPWAP) tunnel. An attacker could exploit this vulnerability by sending crafted wireless packets to an affected AP. A successful exploit could allow the attacker to trigger a security violation on the adjacent switch port, which could result in a DoS condition.\r\n\r\n\r\nNote: Though the Common Vulnerability Scoring System (CVSS) score corresponds to a High Security Impact Rating (SIR), this vulnerability is considered Medium because a workaround is available and exploitation requires a specific switch configuration.\r\n\r\nThere are 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-20190417-air-ap-dos [\"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190417-air-ap-dos\"]",
        "title": "Summary"
      },
      {
        "category": "general",
        "text": "This vulnerability affects the following Cisco products if they are running a vulnerable software release:\r\n\r\nAironet 1540 Series APs\r\nAironet 1560 Series APs\r\nAironet 1800 Series APs\r\nAironet 2800 Series APs\r\nAironet 3800 Series APs\r\nAironet 4800 APs\r\nCatalyst 9100 APs\r\n\r\nFor information about affected software releases, consult the Cisco bug ID(s) at the top of this advisory.",
        "title": "Vulnerable Products"
      },
      {
        "category": "general",
        "text": "Only products listed in the Vulnerable Products [\"#vp\"] section of this advisory are known to be affected by this vulnerability.",
        "title": "Products Confirmed Not Vulnerable"
      },
      {
        "category": "general",
        "text": "This vulnerability is exploitable only if the switch port adjacent to the AP is configured with port security and set to shut down when a violation is detected. In that case, client traffic is not encapsulated in a CAPWAP tunnel, so the switch will learn additional MAC addresses on the switch interface where the AP is connected. Once the limit for MAC addresses is reached, a security violation is triggered.\r\n\r\nBy default, port security is disabled. When it is enabled, shutdown is the default security violation mode.",
        "title": "Details"
      },
      {
        "category": "general",
        "text": "Administrators can configure the switch interface with port security to learn only one MAC address (the switch learns the AP MAC address during AP bootup) and, in case of a security violation, to drop any new learned MAC addresses. Using the CLI, configure the security violation mode to either protect or restrict, as in the following example:\r\n\r\n\r\n# configuration terminal\r\n# interface interface_id  # switchport port-security violation {protect | restrict}\r\n\r\nNote: CLI commands may vary slightly by switch model.",
        "title": "Workarounds"
      },
      {
        "category": "general",
        "text": "For information about fixed software releases, consult the Cisco bug ID(s) at the top of this advisory.\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.",
        "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 Aironet Series Access Points Denial of Service Vulnerability",
        "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190417-air-ap-dos"
      },
      {
        "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-20190417-air-ap-dos",
        "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190417-air-ap-dos"
      },
      {
        "category": "external",
        "summary": "Cisco Security Advisories and Alerts page",
        "url": "https://www.cisco.com/go/psirt"
      },
      {
        "category": "external",
        "summary": "Security Vulnerability Policy",
        "url": "https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html"
      }
    ],
    "title": "Cisco Aironet Series Access Points Denial of Service Vulnerability",
    "tracking": {
      "current_release_date": "2020-05-11T15:39:50+00:00",
      "generator": {
        "date": "2022-09-03T03:02:46+00:00",
        "engine": {
          "name": "TVCE"
        }
      },
      "id": "cisco-sa-20190417-air-ap-dos",
      "initial_release_date": "2019-04-17T16:00:00+00:00",
      "revision_history": [
        {
          "date": "2019-04-16T16:39:41+00:00",
          "number": "1.0.0",
          "summary": "Initial public release."
        },
        {
          "date": "2020-05-11T15:39:50+00:00",
          "number": "1.1.0",
          "summary": "Added bug ID with a more complete fix. Added Aironet 4800 APs and Catalyst 9100 APs to Affected Products due to change in impacted software versions."
        }
      ],
      "status": "final",
      "version": "1.1.0"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "category": "product_family",
            "name": "Cisco Aironet Access Point Software",
            "product": {
              "name": "Cisco Aironet Access Point Software ",
              "product_id": "CSAFPID-190024"
            }
          }
        ],
        "category": "vendor",
        "name": "Cisco"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2019-1834",
      "ids": [
        {
          "system_name": "Cisco Bug ID",
          "text": "CSCvj96316"
        },
        {
          "system_name": "Cisco Bug ID",
          "text": "CSCvm97169"
        },
        {
          "system_name": "Cisco Bug ID",
          "text": "CSCvq46817"
        }
      ],
      "notes": [
        {
          "category": "other",
          "text": "Complete.",
          "title": "Affected Product Comprehensiveness"
        }
      ],
      "product_status": {
        "known_affected": [
          "CSAFPID-190024"
        ]
      },
      "release_date": "2019-04-17T16:00:00+00:00",
      "remediations": [
        {
          "category": "vendor_fix",
          "details": "Cisco has released software updates that address this vulnerability.",
          "product_ids": [
            "CSAFPID-190024"
          ],
          "url": "https://software.cisco.com"
        },
        {
          "category": "workaround",
          "details": "Administrators can configure the switch interface with port security to learn only one MAC address (the switch learns the AP MAC address during AP bootup) and, in case of a security violation, to drop any new learned MAC addresses. Using the CLI, configure the security violation mode to either protect or restrict, as in the following example:\r\n\r\n\r\n# configuration terminal\r\n# interface interface_id  # switchport port-security violation {protect | restrict}\r\n\r\nNote: CLI commands may vary slightly by switch model.",
          "product_ids": [
            "CSAFPID-190024"
          ]
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 7.4,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H",
            "version": "3.0"
          },
          "products": [
            "CSAFPID-190024"
          ]
        }
      ],
      "title": "Cisco Aironet Series Access Points Denial of Service Vulnerability"
    }
  ]
}