{"id":"CVE-2021-1420","aliases":["EUVD-2021-6887","GHSA-328f-3qhj-7364"],"status":"published","title":"Cisco Webex Meetings HTML Injection Vulnerability","description":"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.","severity":{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00958,"percentile":0.619,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-80"],"published":"2021-04-08T04:06:37Z","modified":"2026-06-17T03:31:44Z","products":[{"vendor":"cisco","product":"cisco webex meetings"},{"vendor":"cisco","product":"webex_meetings"}],"references":[{"url":"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-webex-VObwRKWV","tags":["vendor-advisory","x_refsource_CISCO","x_transferred","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-1420"},{"url":"https://github.com/advisories/GHSA-328f-3qhj-7364"}],"sources":{"cve":[{"id":"CVE-2021-1420","title":"Cisco Webex Meetings HTML Injection Vulnerability","description":"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.","status":"published","published":"2021-04-08T04:06:37.588Z","modified":"2024-11-08T23:27:36.041Z","cvss":[{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-80"],"updated_at":"2026-11-02T14:33:08.045407Z"}],"euvd":[{"id":"EUVD-2021-6887","description":"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.","status":"published","published":"2021-04-08T04:06:37Z","modified":"2024-11-08T23:27:36Z","cvss":[{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N","level":"medium"}],"updated_at":"2026-11-03T00:05:05.926487Z"}],"ghsa":[{"id":"GHSA-328f-3qhj-7364","title":"A vulnerability in certain web pages of Cisco Webex Meetings could allow an unauthenticated,...","description":"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.","status":"published","published":"2022-05-24T17:46:52Z","modified":"2023-01-29T05:06:17Z","cwes":["CWE-80"],"updated_at":"2026-11-02T14:45:59.496932Z"}],"nvd":[{"id":"CVE-2021-1420","description":"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.","status":"published","published":"2021-04-08T04:15:13.327Z","modified":"2026-06-17T03:31:44.08Z","cvss":[{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N","level":"medium","assessor":"secondary"},{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N","level":"medium","assessor":"primary"},{"version":"2.0","score":4.3,"vector":"AV:N/AC:M/Au:N/C:N/I:P/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-80"],"updated_at":"2026-11-02T14:06:51.610648Z"}]}}