ESB-2018.0908 - [Cisco] Cisco Integrated Services Module for VPN (ISM-VPN): Denial of service - Remote/unauthenticated 2018-03-29

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             AUSCERT External Security Bulletin Redistribution

       Cisco IOS Software Integrated Services Module for VPN Denial
                         of Service Vulnerability
                               29 March 2018


        AusCERT Security Bulletin Summary

Product:           Cisco Integrated Services Module for VPN (ISM-VPN)
Publisher:         Cisco Systems
Operating System:  Cisco
Impact/Access:     Denial of Service -- Remote/Unauthenticated
Resolution:        Patch/Upgrade
CVE Names:         CVE-2018-0154  

Original Bulletin:

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

Cisco Security Advisory

Cisco IOS Software Integrated Services Module for VPN Denial of Service


Advisory ID:     cisco-sa-20180328-dos

First Published: 2018 March 28 16:00 GMT

Version 1.0:     Final

Workarounds:     No workarounds available

Cisco Bug IDs:



CVSS Score:


  o A vulnerability in the crypto engine of the Cisco Integrated Services
    Module for VPN (ISM-VPN) running Cisco IOS Software could allow an
    unauthenticated, remote attacker to cause a denial of service (DoS)
    condition on an affected device.

    The vulnerability is due to insufficient handling of VPN traffic by the
    affected device. An attacker could exploit this vulnerability by sending
    crafted VPN traffic to an affected device. A successful exploit could allow
    the attacker to cause the affected device to hang or crash, resulting in a
    DoS condition.

    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:

    This 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

Affected Products

  o Vulnerable Products

    This vulnerability affects Cisco devices that have a Cisco ISM-VPN
    installed and are running a vulnerable release of Cisco IOS Software.

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

    To determine whether a Cisco ISM-VPN is installed on a device,
    administrators can use the show crypto engine brief command in the CLI. The
    following example shows the output of the command for a Cisco 3900
    Integrated Services Router that has a Cisco ISM-VPN installed:

        ISR3900-ISM# show crypto engine brief
                crypto engine name:  Virtual Private Network (VPN) Module
                crypto engine type:  hardware
                             State:  Enabled
                          Location:  slot 0
                      Product Name:  ISM VPN Accelerator     <<<<<<<<<================
                      UBOOT Ver   :  U-Boot 1.1.1 - ISRG2-Crypto-Engine - Version 2.7 (Build time: Mar  7 2011 - 09:12:23)
                      Firmware Ver:    User: shrtrive - View/Label: REVENTON_FW_COMMIT_IOS_051315 - Date: May 13 2015 - Time: 12:09:51

                      HW State    :  READY
                       Compression:  No
                               DES:  Yes
                             3 DES:  Yes
                           AES CBC:  Yes (128,192,256)
                          AES CNTR:  No
             Maximum buffer length:  4096
                  Maximum DH index:  5120
                  Maximum SA index:  5120
                Maximum Flow index:  10230
              Maximum RSA key size:  2048

                crypto engine name:  Cisco VPN Software Implementation
                crypto engine type:  software
                     serial number:  1810917E
               crypto engine state:  installed
             crypto engine in slot:  N/A


    Determining the Cisco IOS Software Release

    To determine which Cisco IOS 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 Software, the system banner displays text similar to
    Cisco Internetwork Operating System Software or Cisco IOS Software. The
    banner also displays the installed image name in parentheses, followed by
    the Cisco IOS Software release number and release name. Some Cisco devices
    do not support the show version command or may provide different output.

    The following example shows the output of the command for a device that is
    running Cisco IOS Software Release 15.5(2)T1 and has an installed image
    name of C2951-UNIVERSALK9-M:

        Router> show version

        Cisco IOS Software, C2951 Software (C2951-UNIVERSALK9-M), Version 15.5(2)T1, RELEASE SOFTWARE (fc1)
        Technical Support:
        Copyright (c) 1986-2015 by Cisco Systems, Inc.
        Compiled Mon 22-Jun-15 09:32 by prod_rel_team

    For information about the naming and numbering conventions for Cisco IOS
    Software releases, see the Cisco IOS and NX-OS Software Reference Guide.

    Products Confirmed Not Vulnerable

    No other Cisco products are currently known to be affected by this

    Cisco has confirmed that this vulnerability does not affect Cisco IOS XE
    Software, Cisco IOS XR Software, or Cisco NX-OS Software.


  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 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:

    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.

    When 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, 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

    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:

    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

    Cisco IOS Software

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

    Customers can use this tool to perform the following tasks:

       Initiate 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
       Enter the output of the show version command for the tool to parse
       Create a custom search by including all previously published Cisco
        Security Advisories, a specific advisory, or all advisories in the most
        recent bundled publication

    To determine whether a release is affected by any published Cisco Security
    Advisory, use the Cisco IOS Software Checker on or enter a
    Cisco IOS Software release--for example, 15.1(4)M2--in the following field:

    [                    ] [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.


  o This vulnerability was found during the resolution of a Cisco TAC support

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 2018 Semiannual Cisco IOS and IOS XE Software
    Security Advisory Bundled Publication
    Cisco Security Blog: Cisco IOS and IOS XE Software Bundled Publication
    March 2018



Revision History

    | Version  |        Description         | Section  | Status  |      Date      |
    | 1.0      | Initial public release.    | --       | Final   | 2018-March-28  |

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