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             AUSCERT External Security Bulletin Redistribution

     Cisco Webex Teams Adaptive Cards Denial of Service Vulnerability
                              28 January 2020


        AusCERT Security Bulletin Summary

Product:           Cisco Webex Teams
Publisher:         Cisco Systems
Operating System:  Windows
Impact/Access:     Denial of Service -- Existing Account
Resolution:        Patch/Upgrade
CVE Names:         CVE-2020-3131  

Original Bulletin: 

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

Cisco Webex Teams Adaptive Cards Denial of Service Vulnerability

Priority:        Medium

Advisory ID:     cisco-sa-webex-cards-dos-FWzNcXPq

First Published: 2020 January 22 16:00 GMT

Version 1.0:     Final

Workarounds:     No workarounds availableCisco Bug IDs:   CSCvs25793



CVSS Score:


  o [CVE-2020-3131_su]

    A vulnerability in the Cisco Webex Teams client for Windows could allow an
    authenticated, remote attacker to cause the client to crash, resulting in a
    denial of service (DoS) condition. The attacker needs a valid developer
    account to exploit this vulnerability.

    The vulnerability is due to insufficient input validation when processing
    received adaptive cards. The attacker could exploit this vulnerability by
    sending an adaptive card with malicious content to an existing user of the
    Cisco Webex Teams client for Windows. A successful exploit could allow the
    attacker to cause the targeted user's client to crash continuously.

    Cisco has released software updates that address the vulnerability
    described in this advisory. There are no workarounds that address this

    This advisory is available at the following link:


Affected Products

  o [CVE-2020-3131_ap]


    Vulnerable Products


    This vulnerability was introduced in Cisco Webex Teams client for Windows
    Release 3.0.13131.

    See the Details section in the bug ID(s) at the top of this advisory for
    the most complete and current information.


    Products Confirmed Not Vulnerable


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



  o [CVE-2020-3131_wa]

    There are no workarounds that address this vulnerability.


Fixed Software

  o [CVE-2020-3131_fs]

    Cisco has released 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: https://www.cisco.com/c/en/us/products/



    Fixed Releases

    At the time of publication, Cisco Webex Teams client for Windows releases
    3.0.14234 and later contained the fix for this vulnerability.

    See the Details section in the bug ID(s) at the top of this advisory for
    the most complete and current information.


Exploitation and Public Announcements

  o [CVE-2020-3131_ex]

    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 [CVE-2020-3131_vs]

    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.


  o https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/

Revision History

  o +----------+---------------------------+----------+--------+--------------+
    | Version  |        Description        | Section  | Status |     Date     |
    | 1.0      | Initial public release.   | -        | Final  | 2020-JAN-22  |

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

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