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             AUSCERT External Security Bulletin Redistribution             
                                                                           
                               ESB-2024.1834                               
  Cisco IOS and IOS XE Software Locator ID Separation Protocol Denial of   
                           Service Vulnerability                           
                               28 March 2024                               
                                                                           
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        AusCERT Security Bulletin Summary
        ---------------------------------

Product:           Cisco IOS Software                                      
                   Cisco IOS XE Software                                   
Publisher:         Cisco Systems                                           
Operating System:  Cisco                                                   
Resolution:        Patch/Upgrade                                           
CVE Names:         CVE-2024-20311                                          

Original Bulletin:
   https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-lisp-3gYXs3qP

Comment: CVSS (Max):  8.6 CVE-2024-20311 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H)
         CVSS Source: Cisco Systems                                        
         Calculator:  https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H


- --------------------------BEGIN INCLUDED TEXT--------------------

Cisco IOS and IOS XE Software Locator ID Separation Protocol Denial of Service
Vulnerability

Priority:        High
Advisory ID:     cisco-sa-lisp-3gYXs3qP
First Published: 2024 March 27 16:00 GMT
Version 1.0:     Final
Workarounds:     No workarounds available
Cisco Bug IDs:   CSCwf36266
CVE Names:       CVE-2024-20311
CWEs:            CWE-674

Summary

  o A vulnerability in the Locator ID Separation Protocol (LISP) feature of
    Cisco IOS Software and Cisco IOS XE Software could allow an
    unauthenticated, remote attacker to cause an affected device to reload.

    This vulnerability is due to the incorrect handling of LISP packets. An
    attacker could exploit this vulnerability by sending a crafted LISP packet
    to an affected device. A successful exploit could allow the attacker to
    cause the device to reload, resulting in a denial of service (DoS)
    condition.

    Note: This vulnerability could be exploited over either IPv4 or IPv6
    transport.

    Cisco has released software updates that address this vulnerability. There
    are no workarounds that address this vulnerability.

    This advisory is available at the following link:
    https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-lisp-3gYXs3qP

    This advisory is part of the March 2024 release of the Cisco IOS and IOS XE
    Software Security Advisory Bundled Publication. For a complete list of the
    advisories and links to them, see Cisco Event Response: March 2024
    Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled
    Publication .

Affected Products

  o Vulnerable Products

    This vulnerability affects Cisco devices if they are running a vulnerable
    release of Cisco IOS or IOS XE Software, they have the LISP feature
    enabled, and they are configured with one of the following:

       Ingress/egress tunnel router
       Map server
       Map resolver

    Determine Whether LISP is Enabled

    To determine whether a device is configured with LISP, use the show
    running-config | include router lisp command. If the command returns
    output, as shown in the following example, the device is affected by this
    vulnerability:

        Router# show running-config | include router lisp
        router lisp
        Router#

    For information about which Cisco software releases are vulnerable, see the
    Fixed Software section of this advisory.

    Products Confirmed Not Vulnerable

    Only products listed in the Vulnerable Products section of this advisory
    are known to be affected by this vulnerability.

    Cisco has confirmed that this vulnerability does not affect the following
    Cisco products:

       IOS XR Software
       Meraki products
       NX-OS Software

Workarounds

  o There are no workarounds that address this vulnerability.

Fixed Software

  o Cisco has released free software updates 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.

    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:
    https://www.cisco.com/c/en/us/products/end-user-license-agreement.html

    Additionally, 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.

    The Cisco Support and Downloads page 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.

    When considering software upgrades , customers are advised to regularly
    consult the advisories for Cisco products, which are available from the
    Cisco Security Advisories page , to determine exposure and a complete
    upgrade solution.

    In 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.

    Customers Without Service Contracts

    Customers 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

    Customers 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.

    Cisco IOS and IOS XE Software

    To help customers determine their exposure to vulnerabilities in Cisco IOS
    and IOS XE Software, Cisco provides the Cisco Software Checker . This tool
    identifies any Cisco security advisories that impact a specific software
    release and the earliest release that fixes the vulnerabilities that are
    described in each advisory ("First Fixed"). If applicable, the tool also
    returns the earliest release that fixes all the vulnerabilities that are
    described in all the advisories that the Software Checker identifies
    ("Combined First Fixed").

    To use the tool, go to the Cisco Software Checker page and follow the
    instructions. Alternatively, use the following form to determine whether a
    release is affected by any Cisco Security Advisory. To use the form, follow
    these steps:

     1. Choose which advisories the tool will search-only this advisory, only
        advisories with a Critical or High Security Impact Rating (SIR) , or
        all advisories.
     2. Enter a release number-for example, 15.9(3)M2 or 17.3.3.
     3. Click Check .

    [2                   ] [                    ] [Critical,High,Medium] 
    [Only this advisory              ]

    [                    ] [Check]

Exploitation and Public Announcements

  o 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.

Source

  o This vulnerability was found during internal security testing by X.B. of
    the Cisco Advanced Security Initiatives Group (ASIG).

Cisco Security Vulnerability Policy

  o To learn about Cisco security vulnerability disclosure policies and
    publications, see the Security Vulnerability Policy . This document also
    contains instructions for obtaining fixed software and receiving security
    vulnerability information from Cisco.

Subscribe to Cisco Security Notifications

  o Subscribe

Related to This Advisory

  o Cisco Event Response: March 2024 Semiannual Cisco IOS and IOS XE Software
    Security Advisory Bundled Publication

URL

  o https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-lisp-3gYXs3qP

Revision History

  o +----------+---------------------------+----------+--------+--------------+
    | Version  |        Description        | Section  | Status |     Date     |
    +----------+---------------------------+----------+--------+--------------+
    | 1.0      | Initial public release.   | -        | Final  | 2024-MAR-27  |
    +----------+---------------------------+----------+--------+--------------+

Legal Disclaimer

  o 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.

    A 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.

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