ESB-2018.0901 - [Cisco] Cisco IOS XE: Root compromise - Existing account 2018-03-29

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             AUSCERT External Security Bulletin Redistribution

                               ESB-2018.0901
     Cisco IOS XE Software EXEC Mode Root Shell Access Vulnerabilities
                               29 March 2018

===========================================================================

        AusCERT Security Bulletin Summary
        ---------------------------------

Product:           Cisco IOS XE
Publisher:         Cisco Systems
Operating System:  Cisco
Impact/Access:     Root Compromise -- Existing Account
Resolution:        Patch/Upgrade
CVE Names:         CVE-2018-0184 CVE-2018-0183 CVE-2018-0176
                   CVE-2018-0169  

Original Bulletin: 
   https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-privesc1
   https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-privesc2
   https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-privesc3

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

Cisco Security Advisory

Cisco IOS XE Software User EXEC Mode Root Shell Access Vulnerabilities

High

Advisory ID:     cisco-sa-20180328-privesc1

First Published: 2018 March 28 16:00 GMT

Version 1.0:     Final

Workarounds:     No workarounds available

Cisco Bug IDs:
CSCtw85441
CSCus42252
CSCuv95370

CVE-2018-0169
CVE-2018-0176

CWE-264

CVSS Score:
7.8  AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:X/RL:X/RC:X

Summary

  o Multiple vulnerabilities in the CLI parser of Cisco IOS XE Software could
    allow an authenticated, local attacker to gain access to the underlying
    Linux shell of an affected device and execute arbitrary commands with root
    privileges on the device.

    The vulnerabilities are due to the affected software improperly sanitizing
    command arguments to prevent access to internal data structures on a
    device. An attacker who has user EXEC mode (privilege level 1) access to an
    affected device could exploit these vulnerabilities on the device by
    executing CLI commands that contain crafted arguments. A successful exploit
    could allow the attacker to gain access to the underlying Linux shell of
    the affected device and execute arbitrary commands with root privileges on
    the device.

    Cisco has released software updates that address these vulnerabilities.
    There are no workarounds that address these vulnerabilities.

    This advisory is available at the following link:
    https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/
    cisco-sa-20180328-privesc1

    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
    Publication.

Affected Products

  o Vulnerable Products

    These vulnerabilities affect Cisco devices that are running a vulnerable
    release of Cisco IOS XE Software.

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

    Determining the Cisco IOS XE Software Release

    To 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.

    The 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:

        ios-xe-device# show version

        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
        .
        .
        .

    For information about the naming and numbering conventions for Cisco IOS XE
    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 these
    vulnerabilities.

    Cisco has confirmed that these vulnerabilities do not affect Cisco IOS
    Software, Cisco IOS XR Software, or Cisco NX-OS Software.

Workarounds

  o There are no workarounds that address these vulnerabilities.

Fixed Software

  o Cisco has released free software updates that address the vulnerabilities
    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:
    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.

    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
    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 a tool, the Cisco IOS Software Checker,
    that identifies any Cisco Security Advisories that impact a specific
    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 Cisco.com or enter a
    Cisco IOS Software or Cisco IOS XE Software release--for example, 15.1(4)M2
    or 3.13.8S--in the following field:

    [                    ] [Check]

    For a mapping of Cisco IOS XE Software releases to Cisco IOS Software
    releases, refer to the Cisco IOS XE 2 Release Notes, Cisco IOS XE 3S
    Release Notes, or Cisco IOS XE 3SG Release Notes, depending on the
    Cisco IOS XE Software release.

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 vulnerabilities that are
    described in this advisory.

Source

  o These vulnerabilities were found during internal security testing.

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

URL

  o https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-privesc1

Revision History

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


======================================================

Cisco Security Advisory

Cisco IOS XE Software Privileged EXEC Mode Root Shell Access Vulnerability

Medium

Advisory ID:     cisco-sa-20180328-privesc2

First Published: 2018 March 28 16:00 GMT

Version 1.0:     Final

Workarounds:     No workarounds available

Cisco Bug IDs:
CSCve74432

CVE-2018-0184

CWE-264

CVSS Score:
6.7  AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:X/RL:X/RC:X

Summary

  o A vulnerability in the CLI parser of Cisco IOS XE Software could allow an
    authenticated, local attacker to gain access to the underlying Linux shell
    of an affected device and execute arbitrary commands with root privileges
    on the device.

    The vulnerability is due to the affected software improperly sanitizing
    command arguments to prevent access to internal data structures on a
    device. An attacker who has privileged EXEC mode (privilege level 15)
    access to an affected device could exploit this vulnerability on the device
    by executing CLI commands that contain crafted arguments. A successful
    exploit could allow the attacker to gain access to the underlying Linux
    shell of the affected device and execute arbitrary commands with root
    privileges on the device.

    There are no workarounds that address this vulnerability.

    This advisory is available at the following link:
    https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/
    cisco-sa-20180328-privesc2

Affected Products

  o Vulnerable Products

    This vulnerability affects Cisco devices that are running a vulnerable
    release of Cisco IOS XE Software.

    For information about which Cisco IOS XE Software releases are vulnerable,
    consult the Cisco bug ID(s) at the top of this advisory.

    Determining the Cisco IOS XE Software Release

    To 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.

    The 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:

        ios-xe-device# show version

        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
        .
        .
        .

    For information about the naming and numbering conventions for Cisco IOS XE
    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
    vulnerability.

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

Workarounds

  o There are no workarounds that address this vulnerability.

Fixed Software

  o For detailed information about fixed software releases, consult the Cisco
    bug ID(s) at the top of this advisory.

    For a mapping of Cisco IOS XE Software releases to Cisco IOS Software
    releases, refer to the Cisco IOS XE 2 Release Notes, Cisco IOS XE 3S
    Release Notes, or Cisco IOS XE 3SG Release Notes, depending on the
    Cisco IOS XE Software release.

    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
    providers.

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.

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

URL

  o https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-privesc2

Revision History

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


======================================================

Cisco Security Advisory

Cisco IOS XE Software for Cisco 4000 Series Integrated Services Routers
Privileged EXEC Mode Root Shell Access Vulnerability

Medium

Advisory ID:     cisco-sa-20180328-privesc3

First Published: 2018 March 28 16:00 GMT

Version 1.0:     Final

Workarounds:     No workarounds available

Cisco Bug IDs:
CSCuv91356

CVE-2018-0183

CWE-264

CVSS Score:
6.7  AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:X/RL:X/RC:X

Summary

  o A vulnerability in the CLI parser of Cisco IOS XE Software could allow an
    authenticated, local attacker to gain access to the underlying Linux shell
    of an affected device and execute arbitrary commands with root privileges
    on the device.

    The vulnerability is due to the affected software improperly sanitizing
    command arguments to prevent access to internal data structures on a
    device. An attacker who has privileged EXEC mode (privilege level 15)
    access to an affected device could exploit this vulnerability on the device
    by executing CLI commands that contain crafted arguments. A successful
    exploit could allow the attacker to gain access to the underlying Linux
    shell of the affected device and execute arbitrary commands with root
    privileges on the device.

    There are no workarounds that address this vulnerability.

    This advisory is available at the following link:
    https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/
    cisco-sa-20180328-privesc3

Affected Products

  o Vulnerable Products

    This vulnerability affects Cisco 4000 Series Integrated Services Routers
    that are running a vulnerable release of Cisco IOS XE Software.

    For information about which Cisco IOS XE Software releases are vulnerable,
    consult the Cisco bug ID(s) at the top of this advisory.

    Determining the Cisco IOS XE Software Release

    To 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.

    The 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:

        ios-xe-device# show version

        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
        .
        .
        .

    For information about the naming and numbering conventions for Cisco IOS XE
    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
    vulnerability.

    Cisco has confirmed that this vulnerability does not affect other Cisco
    products that are running Cisco IOS XE Software.

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

Workarounds

  o There are no workarounds that address this vulnerability.

Fixed Software

  o For detailed information about fixed software releases, consult the Cisco
    bug ID(s) at the top of this advisory.

    For a mapping of Cisco IOS XE Software releases to Cisco IOS Software
    releases, refer to the Cisco IOS XE 2 Release Notes, Cisco IOS XE 3S
    Release Notes, or Cisco IOS XE 3SG Release Notes, depending on the
    Cisco IOS XE Software release.

    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
    providers.

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.

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

URL

  o https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-privesc3

Revision History

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

- --------------------------END INCLUDED TEXT--------------------

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