Cisco TelePresence Collaboration Endpoint and RoomOS Software H.323 Denial of Service Vulnerability

Advisory ID:cisco-sa-ce-roomos-dos-c65x2Qf2
First Published:2022 April 20 16:00 GMT
Version 1.0:Final
Workarounds:No workarounds available
Cisco Bug IDs:CSCvz55702
CVSS Score:Base 7.5
CVE-2022-20783CWE-1287 Download CVRFEmail


  • A vulnerability in the packet processing functionality of Cisco TelePresence Collaboration Endpoint (CE) Software and Cisco RoomOS Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.This vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by sending crafted H.323 traffic to an affected device. A successful exploit could allow the attacker to cause the affected device to either reboot normally or reboot into maintenance mode, which could result in a DoS condition on the device.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:

Affected Products

  • Vulnerable ProductsThis vulnerability affects Cisco RoomOS Software in Cloud-Aware On-Premises operation, which is cloud based, and Cisco TelePresence CE Software if they are running vulnerable releases and have H.323 Mode enabled.Note: H.323 Mode is disabled by default.For information about which Cisco software releases are vulnerable, see the Fixed Software section of this advisory.Determine the Device ConfigurationTo determine whether H.323 Mode is enabled in Cisco TelePresence CE Software, log in to the device and navigate to the Network Services section of the Setup > Configuration interface. If the H.323 Mode option is set to On, the device is vulnerable.To determine whether a device has H.323 Mode enabled in RoomOS Software for Cloud-Aware Devices, log in to Cisco Control Hub and perform the following steps:
    1. Choose Devices.
    2. Search for Cloud-Aware devices using the query Calling == Premises Calling on the Devices screen.
    3. Select a device to check.
    4. Select All configurations under Configurations.
    5. Select NetworkServices > H323 > Mode.
    6. Verify H323 Mode. If the setting is off, the device is not vulnerable. If the setting is on, the device is vulnerable.
    Products Confirmed Not VulnerableOnly 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 Cisco RoomOS Software in Cloud-Only operation because H.323 Mode is not available.


  • There are no workarounds that address this vulnerability.

Fixed Software

  • 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:, 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 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 ContractsCustomers 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: 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.Fixed ReleasesIn the following table(s), the left column lists Cisco software releases. The right column indicates whether a release is affected by the vulnerability described in this advisory and the first release that includes the fix for this vulnerability. Customers are advised to upgrade to an appropriate fixed software release as indicated in this section.Cisco TelePresence CE Software ReleaseFirst Fixed ReleaseEarlier than 9Migrate to a fixed release. has addressed this vulnerability in Cisco RoomOS, which is cloud based. No user action is required. Customers can determine the current remediation status or software version by using the Help function in the service GUI. Customers who need additional information are advised to contact the Cisco Technical Assistance Center (TAC) or their contracted maintenance providers.Cisco RoomOS SoftwareFirst Fixed ReleaseEarlier than RoomOS January 2022RoomOS January 2022The Cisco Product Security Incident Response Team (PSIRT) validates only the affected and fixed release information that is documented in this advisory.

Exploitation and Public Announcements

  • The Cisco 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 the National Security Agency (NSA) for reporting this vulnerability.


Leave a Reply

Your email address will not be published. Required fields are marked *