Cisco Webex Meetings API Cross-Site Scripting Vulnerability

published 2020-11-18 5 y ago modified 2026-06-17 4 mo ago also EUVD-2020-19650

cvss: 6.1; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.0%; EPSS 1.0% chance of exploitation in 30 days, percentile 63%
public exploits: 0; none known

A vulnerability in an API of Cisco Webex Meetings could allow an unauthenticated, remote attacker to conduct cross-site scripting attacks. The vulnerability is due to improper validation of user-supplied input to an application programmatic interface (API) within Cisco Webex Meetings. An attacker could exploit this vulnerability by convincing a targeted user to follow a link designed to submit malicious input to the API used by Cisco Webex Meetings. A successful exploit could allow the attacker to conduct cross-site scripting attacks and potentially gain access to sensitive browser-based information from the system of a targeted user.

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 23 mo ago (2024-11-13)

Exploit prediction

1.02% chance of exploitation in the next 30 days, higher than 63% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	6.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
NVD	3.1	6.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
NVD	2.0	4.3	AV:N/AC:M/Au:N/C:N/I:P/A:N

Affected products

Cisco Cisco Webex Meetings

Classification

Weakness

CWE-80 Improper Neutralization of Script-Related HTML Tags in a Web Page
CWE-79 Improper Neutralization of Input During Web Page Generation

References

tools.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-webex-meetings-xss-MX56prER
vendor-advisory

Sources

CVE List CVE-2020-27126
NVD CVE-2020-27126

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Summary