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Fencer Vulns
medium 4.7

CVE-2021-1420 json

Cisco Webex Meetings HTML Injection Vulnerability

published 2021-04-08 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-6887

cvss
4.7
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 61%
public exploits
0
none known

Summary

A vulnerability in certain web pages of Cisco Webex Meetings could allow an unauthenticated, remote attacker to modify a web page in the context of a user's browser. The vulnerability is due to improper checks on parameter values in affected pages. An attacker could exploit this vulnerability by persuading a user to follow a crafted link that is designed to pass HTML code into an affected parameter. A successful exploit could allow the attacker to alter the contents of a web page to redirect the user to potentially malicious websites, or the attacker could use this vulnerability to conduct further client-side attacks.

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
2 y ago

Exploit prediction

0.96% chance of exploitation in the next 30 days, higher than 61% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 4.7 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N
NVD 3.1 4.7 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/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

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.