CVE-2025-20215
mediumpriority · track · 0EPSS 0.001 · 2 %ileDEEURUUSEPSS · scored 2026-10-27
A vulnerability in the meeting-join functionality of Cisco Webex Meetings could have allowed an unauthenticated, network-proximate attacker to complete a meeting-join process in place of an intended targeted user, provided the requisite conditions were satisfied. Cisco has addressed this vulnerability in the Cisco Webex Meetings service, and no customer action is needed. This vulnerability existed due to client certificate validation issues. Prior to this vulnerability being addressed, an attacker could have exploited this vulnerability by monitoring local wireless or adjacent networks for client-join requests and attempting to interrupt and complete the meeting-join flow as another user who was currently joining a meeting. To successfully exploit the vulnerability, an attacker would need the capability to position themselves in a local wireless or adjacent network, to monitor and intercept the targeted network traffic flows, and to satisfy timing requirements in order to interrupt the meeting-join flow and exploit the vulnerability. A successful exploit could have allowed the attacker to join the meeting as another user. However, the Cisco Product Security Incident Response Team (PSIRT) is not aware of any malicious use of the vulnerability that is described in this advisory.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco Webex Meetingscisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (4)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2025-1733Cisco WebEx Meeting Center: Schwachstelle ermöglicht Umgehen von SicherheitsvorkehrungenDeutsch2025-08-06csaf · cert_bundDE
Ein Angreifer aus einem angrenzenden Netzwerk kann eine Schwachstelle in Cisco WebEx Meeting Center ausnutzen, um Sicherheitsvorkehrungen zu umgehen.
- cisco-sa-webex-join-yNXfqHk4Cisco Webex Meeting Client Join Certificate Validation Vulnerability2025-08-06csaf · cisco_csafUS
A vulnerability in the meeting-join functionality of Cisco Webex Meetings could have allowed an unauthenticated, network-proximate attacker to complete a meeting-join process in place of an intended targeted user, provided the requisite conditions were satisfied. Cisco has addressed this vulnerability in the Cisco Webex Meetings service, and no customer action is needed. This vulnerability existed due to client certificate validation issues. Prior to this vulnerability being addressed, an attacker could have exploited this vulnerability by monitoring local wireless or adjacent networks for client-join requests and attempting to interrupt and complete the meeting-join flow as another user who was currently joining a meeting. To successfully exploit the vulnerability, an attacker would need the capability to position themselves in a local wireless or adjacent network, to monitor and intercept the targeted network traffic flows, and to satisfy timing requirements in order to interrupt the meeting-join flow and exploit the vulnerability. A successful exploit could have allowed the attacker to join the meeting as another user. However, the Cisco Product Security Incident Response Team (PSIRT) is not aware of any malicious use of the vulnerability that is described in this advisory. As mentioned, Cisco has addressed this vulnerability in the Cisco Webex Meetings service, and no customer action is necessary to update on-premises software or devices. There are no workarounds that address this vulnerability.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (3)
External citations — patches, advisories, analysis.
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-webex-join-yNXfqHk4cnnvd
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-webex-join-yNXfqHk4enisa_euvd
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-webex-join-yNXfqHk4nvd
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