{
  "document": {
    "acknowledgments": [
      {
        "summary": "This vulnerability was found during internal security testing."
      }
    ],
    "category": "csaf_security_advisory",
    "csaf_version": "2.0",
    "notes": [
      {
        "category": "summary",
        "title": "Summary",
        "text": "A vulnerability in the boot process of Cisco IOS XR Software could allow an authenticated, local attacker with high privileges to bypass the Cisco Secure Boot functionality and load unverified software on an affected device. To exploit this successfully, the attacker must have root-system privileges on the affected device.\r\n\r\nThis vulnerability is due to an error in the software build process. An attacker could exploit this vulnerability by manipulating the system’s configuration options to bypass some of the integrity checks that are performed during the booting process. A successful exploit could allow the attacker to control the boot configuration, which could enable them to bypass of the requirement to run Cisco signed images or alter the security properties of the running system.\r\n\r\nCisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.\r\n\r\n"
      },
      {
        "category": "general",
        "title": "Vulnerable Products",
        "text": "This vulnerability affects the following Cisco products if they are running Cisco IOS XR Release 24.2.1:\r\n\r\n8000 Series Routers\r\nNCS 1010 Series Routers\r\nNCS 1014 Series Routers\r\nNCS 540 Series Routers that are running the NCS540L images\r\nNCS 5700 Fixed Port Series Routers, excluding NCS-57C3-MOD-S and NCS-57C3-MOD-SE-S\r\n\r\nNote: Cisco IOS XR release 24.2.1 is the only vulnerable release.\r\n\r\nDetermine the Software Release\r\n\r\nTo determine whether the device is running an affected software image, use the show version command in the device CLI. If the output indicates Version 24.2.1 running on an affected product listed above, as shown in the following example, then the device is affected by this vulnerability:\r\n\r\n\r\nRouter# show version\r\nCisco IOS XR Software, Version 24.2.1\r\nCopyright (c) 2013-2024 by Cisco Systems, Inc."
      },
      {
        "category": "general",
        "title": "Products Confirmed Not Vulnerable",
        "text": "Only products listed in the Vulnerable Products [\"#vp\"] section of this advisory are known to be affected by this vulnerability.\r\n\r\nCisco has confirmed that this vulnerability does not affect the following Cisco IOS XR products:\r\n\r\nASR 9000 Series Routers\r\nIOS XRv 9000 Routers\r\nNCS 540 Series Routers  NCS540-ACC-SYS and NCS 540-24Z8Q2C-SYS\r\nNCS 5500 Series Routers\r\nNCS 5700 Fixed Port Series Routers NCS-57C3-MOD-S and NCS-57C3-MOD-SE-S\r\n\r\nCisco has confirmed that this vulnerability does not affect the following Cisco products:\r\n\r\nIOS Software\r\nIOS XE Software\r\nNX-OS Software"
      },
      {
        "category": "general",
        "title": "Workarounds",
        "text": "There are no workarounds that address this vulnerability."
      },
      {
        "category": "general",
        "title": "Fixed Software",
        "text": "Cisco has released free software updates [\"https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html#ssu\"] that address the vulnerability described in this advisory. Customers with service contracts that entitle them to regular software updates should obtain security fixes through their usual update channels.\r\n\r\nCustomers 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\nThe Cisco Support and Downloads page [\"https://www.cisco.com/c/en/us/support/index.html\"] on Cisco.com provides information about licensing and downloads. This page can also display customer device support coverage for customers who use the My Devices tool.\r\n\r\nWhen considering software upgrades [\"https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html#fixes\"], customers are advised to regularly consult the advisories for Cisco products, which are available from the Cisco Security Advisories 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  Customers Without Service Contracts\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: https://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 issue only affects Cisco IOS XR Release 24.2.1 running on the platforms that are listed in the Vulnerable Products section of this advisory. The fixed release is 24.2.11.\r\n\r\nThe Cisco Product Security Incident Response Team (PSIRT) validates only the affected and fixed release information that is documented in this advisory."
      },
      {
        "category": "general",
        "title": "Vulnerability Policy",
        "text": "To learn about Cisco security vulnerability disclosure policies and publications, see the Security Vulnerability Policy [\"http://www.cisco.com/web/about/security/psirt/security_vulnerability_policy.html\"]. This document also contains instructions for obtaining fixed software and receiving security vulnerability information from Cisco."
      },
      {
        "category": "general",
        "title": "Exploitation and Public Announcements",
        "text": "The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory."
      },
      {
        "category": "general",
        "title": "Source",
        "text": "This vulnerability was found during internal security testing."
      },
      {
        "category": "legal_disclaimer",
        "title": "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."
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "psirt@cisco.com",
      "issuing_authority": "Cisco PSIRT",
      "name": "Cisco",
      "namespace": "https://wwww.cisco.com"
    },
    "references": [
      {
        "category": "self",
        "summary": "Cisco IOS XR Software Secure Boot Bypass Vulnerability",
        "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-xr-secure-boot-quD5g8Ap"
      },
      {
        "category": "external",
        "summary": "Cisco Security Vulnerability Policy",
        "url": "https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html"
      },
      {
        "category": "external",
        "summary": "free software updates",
        "url": "https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html#ssu"
      },
      {
        "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 Support and Downloads page",
        "url": "https://www.cisco.com/c/en/us/support/index.html"
      },
      {
        "category": "external",
        "summary": "considering software upgrades",
        "url": "https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html#fixes"
      },
      {
        "category": "external",
        "summary": "Cisco Security Advisories 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": "Security Vulnerability Policy",
        "url": "http://www.cisco.com/web/about/security/psirt/security_vulnerability_policy.html"
      }
    ],
    "title": "Cisco IOS XR Software Secure Boot Bypass Vulnerability",
    "tracking": {
      "current_release_date": "2024-07-10T16:00:00+00:00",
      "generator": {
        "date": "2024-07-10T16:01:11+00:00",
        "engine": {
          "name": "TVCE"
        }
      },
      "id": "cisco-sa-xr-secure-boot-quD5g8Ap",
      "initial_release_date": "2024-07-10T16:00:00+00:00",
      "revision_history": [
        {
          "date": "2024-07-10T16:01:07+00:00",
          "number": "1.0.0",
          "summary": "Initial public release."
        }
      ],
      "status": "final",
      "version": "1.0.0"
    }
  },
  "product_tree": {
    "branches": [
      {
        "name": "Cisco",
        "category": "vendor",
        "branches": [
          {
            "name": "Cisco IOS XR Software",
            "category": "product_family",
            "product": {
              "name": "Cisco IOS XR Software ",
              "product_id": "CSAFPID-5834"
            }
          }
        ]
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2024-20456",
      "ids": [
        {
          "system_name": "Cisco Bug ID",
          "text": "CSCwk58609"
        }
      ],
      "notes": [
        {
          "category": "other",
          "title": "Affected Product Comprehensiveness",
          "text": "Complete."
        }
      ],
      "product_status": {
        "known_affected": [
          "CSAFPID-5834"
        ]
      },
      "release_date": "2024-07-10T16:00:00+00:00",
      "remediations": [
        {
          "category": "vendor_fix",
          "details": "Cisco has released software updates that address this vulnerability.",
          "product_ids": [
            "CSAFPID-5834"
          ],
          "url": "https://software.cisco.com"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 6.7,
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "products": [
            "CSAFPID-5834"
          ]
        }
      ],
      "title": "Cisco IOS XR Softwsare Secure Boot Bypass Vulnerability"
    }
  ]
}