A vulnerability in Cisco Jabber for Windows could allow an authenticated, remote attacker to execute arbitrary code.
The vulnerability is due to improper validation of message contents. An attacker could exploit this vulnerability by sending specially crafted Extensible Messaging and Presence Protocol (XMPP) messages to the affected software. A successful exploit could allow the attacker to cause the application to execute arbitrary programs on the targeted system with the privileges of the user account that is running the Cisco Jabber client software, possibly resulting in arbitrary code execution.
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 vulnerability affects Cisco Jabber for Windows if it is running a vulnerable software release.
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.
This vulnerability does not affect Cisco Jabber for MacOS or Cisco Jabber for mobile platforms.
To exploit this vulnerability, an attacker must be able to send XMPP messages to end-user systems running Cisco Jabber for Windows. Attackers may require access to the same XMPP domain or another method of access to be able to send messages to clients.
As a result of exploitation, an attacker could cause the application to run an arbitrary executable that already exists within the local file path of the application. The executable would run on the end-user system with the privileges of the user who initiated the Cisco Jabber client application.
Systems using Cisco Jabber in phone-only mode without XMPP messaging services enabled are not vulnerable to exploitation. In addition, the vulnerability is not exploitable when Cisco Jabber is configured to use messaging services other than XMPP messaging.
There are no workarounds that address this vulnerability.
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: 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 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.
Customers are advised to upgrade to an appropriate fixed software release as indicated in the following table:
|Cisco Jabber for Windows Release||First Fixed Release|
Exploitation and Public Announcements
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.
Cisco would like to thank Olav Sortland Thoresen of Watchcom for reporting this vulnerability.