What is the CVSS score of CVE-2026-20187?

CVE-2026-20187 has a CVSS 3.1 base score of 7.5 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. EPSS exploitation probability: 0.3%.

Which versions of Cisco RoomOS are affected by CVE-2026-20187?

Cisco RoomOS software powering video collaboration endpoints and room-based devices is susceptible to a denial-of-service attack by unauthenticated remote attackers, potentially disabling meeting…

How to fix or mitigate CVE-2026-20187?

Within 24 hours, inventory all Cisco RoomOS devices in your environment and assess their network accessibility; immediately implement firewall rules and network segmentation to restrict remote access to these endpoints from untrusted networks. Within 7 days, enable comprehensive logging on affected devices, configure alerting for connection anomalies and repeated rejection patterns, and contact your Cisco account team to obtain real-time patch availability notifications. Within 30 days, continuously monitor Cisco RoomOS security advisories and customer notifications for patch announcements; establish a test environment and staged deployment plan to validate and roll out patches to production systems as soon as vendor release is available.

Cisco RoomOS CVE-2026-20187

EUVD-2026-44722 HIGH

Improper Check or Handling of Exceptional Conditions (CWE-703)

2026-07-15 cisco

GHSA-xmhm-hhwr-f9fp

Cisco Information Disclosure Cisco Roomos Software

7.5

CVSS 3.1 · Vendor: cisco

Severity by source

Vendor (cisco) PRIMARY

7.5 HIGH

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

vuln.today AI

7.5 HIGH

Network-reachable service exploitable without auth or interaction at low complexity, causing availability loss only, so C:N/I:N/A:H with PR:N/UI:N matches the disclosed DoS impact.

3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Primary rating from Vendor (cisco).

CVSS VectorVendor: cisco

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Lifecycle Timeline

Analysis Generated

Jul 15, 2026 - 16:49 vuln.today

CVE Published

Jul 15, 2026 - 16:18 cve.org

HIGH 7.5

DescriptionCVE.org

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco RoomOS engineering team has conducted a comprehensive internal security review. This review resulted in a software hardening release that addresses multiple internally discovered vulnerabilities.

The vulnerabilities tracked by CVE-2026-20187 are related to improper handling of exceptional conditions that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-703.

AnalysisAI

Denial of service in Cisco RoomOS software allows remote unauthenticated attackers to exhaust availability of affected collaboration endpoints and room-based video devices through improper handling of exceptional conditions (CWE-703). The issue was internally discovered by Cisco's RoomOS engineering team as part of a hardening release bundling multiple flaws under this identifier, carries a CVSS 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H), and has no public exploit identified at time of analysis. Note that the CVSS vector reflects availability-only impact even though a source tag labels it 'Information Disclosure,' a discrepancy defenders should verify against the Cisco advisory.

Technical ContextAI

Cisco RoomOS is the software platform running on Cisco's Room, Board, and Desk collaboration endpoints (Webex-registered and on-premises video conferencing hardware). The root cause is classified under CWE-703 (Improper Handling of Exceptional Conditions), a pillar-level weakness class describing failures to correctly detect, propagate, or recover from error states, unexpected inputs, or resource-limit conditions. In network-facing services, this class typically manifests as unhandled exceptions or malformed-input parsing paths that crash or hang a process, producing the availability impact reflected in the CVSS vector. The single affected CPE is cpe:2.3:a:cisco:cisco_roomos_software (all versions prior to the hardening release), and CVE-2026-20187 is described by Cisco as an umbrella tracking multiple internally discovered vulnerabilities addressed together.

RemediationAI

Apply the Cisco RoomOS software hardening release that addresses CVE-2026-20187; because RoomOS devices are typically cloud-managed (Webex Control Hub) or receive automatic/scheduled software updates, ensure endpoints are on the latest RoomOS train and that automatic upgrades are enabled so the fixed build is deployed. The input does not include an exact fixed version number, so consult the Cisco advisory (https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-roomos-AqNMbEq) for the precise patched release and confirm your fleet's build against it. As a compensating control until patched, restrict network reachability to the endpoints' management and signaling interfaces - place RoomOS devices on a segmented VLAN, limit inbound access to trusted Webex/on-prem call-control infrastructure, and block untrusted network paths to the devices; the trade-off is that overly aggressive filtering can break call setup, provisioning, or cloud registration, so validate against required Webex service endpoints before enforcing.