CVE-2025-20215
Cisco Webex Meeting Client Join Certificate Validation Vulnerability
Published Aug 6, 2025
CVSS 3.1 · 5.4 Medium
EPSS < 1%
KEV · Not listed
Description
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.
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.
Affected Products
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CVE record
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NVD configurations
No data
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Red Hat packages
No data
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OpenCVE enrichment
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Cisco | Cisco Webex Meetings | affected |
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No data.
No data.
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Webex | — |
| Cisco | Webex Meetings | — |
Remediation
Tracking
Advisories
| Source | ID | Title |
|---|---|---|
 EUVD |
EUVD-2025-23858 | 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. |
Metrics
No CVSS v4.0
Attack Vector Adjacent Network
Attack Complexity High
Privileges Required None
Scope Unchanged
Confidentiality Impact High
Integrity Impact Low
Availability Impact None
User Interaction Required
No CVSS v3.0
No CVSS v2
This CVE is not in the KEV list.
Exploit prediction score: < 1% (0.123% probability within 30 days)
Exploitation none
Automatable no
Technical Impact partial
References
History
Aug 7, 2025 7:30 AM
First appearance in the feed. Affected vendors updated
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Cisco
Cisco webex Cisco webex Meetings |
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| Vendors & Products |
Cisco
Cisco webex Cisco webex Meetings |
Aug 6, 2025 6:15 PM
Scoring metrics updated
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
ssvc
|
Aug 6, 2025 4:30 PM
Description updated. Title updated. Weaknesses updated. Added references. Scoring metrics updated
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| Description | 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. | |
| Title | Cisco Webex Meeting Client Join Certificate Validation Vulnerability | |
| Weaknesses | CWE-295 | |
| References |
| |
| Metrics |
cvssV3_1
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Weaknesses
