CVE-2021-1221

What it is

A vulnerability in the user interface of Cisco Webex Meetings and Cisco Webex Meetings Server Software could allow an authenticated, remote attacker to inject a hyperlink into a meeting invitation email. The vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by entering a URL into a field in the user interface. A successful exploit could allow the attacker to generate a Webex Meetings invitation email that contains a link to a destination of their choosing. Because this email is sent from a trusted source, the recipient may be more likely to click the link.

At a glance

Exploitability

Can be exploited over the network with a low-privilege account, but needs a user to act. Limited direct impact.

Exploit odds

1.0% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2021-02-04 17:15 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 03:31 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 1.0% in the next 30 days (EPSS).
• Severity: 4.1 MEDIUM (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2021-02-04 17:15 UTC

Last modified

2026-06-17 03:31 UTC

Exploit probability

1.0% · EPSS, next 30 days

Weakness

CWE-20 · Improper input validation

Record status

Modified

Affected

• Cisco Webex Meetings < 41.1.0
• Cisco Webex Meetings Server < 3.0
• Cisco Webex Meetings Server 3.0
• Cisco Webex Meetings Server 4.0

Attack profile CVSS 3.1 · 4.1

Attack vector

Network

Complexity

Low

Privileges needed

Low

User interaction

Required

Scope

Changed

Confidentiality

None

Integrity

Low

Availability

None

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2021-1221.md and follow it. Check whether this project is affected by CVE-2021-1221. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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