Cisco Webex Meetings Cross-Site Scripting Vulnerability

published 2021-02-17 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-6818

cvss: 6.1; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.8%; EPSS 0.8% chance of exploitation in 30 days, percentile 57%
public exploits: 0; none known

A vulnerability in the web-based interface of Cisco Webex Meetings could allow an unauthenticated, remote attacker to conduct a cross-site scripting (XSS) attack against a user of the web-based interface of the affected service. The vulnerability is due to insufficient validation of user-supplied input by the web-based interface of the affected service. An attacker could exploit this vulnerability by persuading a user of the interface to click a maliciously crafted link. A successful exploit could allow the attacker to execute arbitrary script code in the context of the affected interface or access sensitive, browser-based information.

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 2 y ago (2024-11-08)

Exploit prediction

0.81% chance of exploitation in the next 30 days, higher than 57% 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-xss-Lz6HbGCt
vendor-advisory

Sources

CVE List CVE-2021-1351
NVD CVE-2021-1351

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Summary