CVE-2021-40126 - CVE House
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Status published Medium CVE-2021-40126

Cisco Umbrella Email Enumeration Vulnerability

Vulnerability Description

A vulnerability in the web-based dashboard of Cisco Umbrella could allow an authenticated, remote attacker to perform an email enumeration attack against the Umbrella infrastructure. This vulnerability is due to an overly descriptive error message on the dashboard that appears when a user attempts to modify their email address when the new address already exists in the system. An attacker could exploit this vulnerability by attempting to modify the user's email address. A successful exploit could allow the attacker to enumerate email addresses of users in the system.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

Cisco Umbrella Insights Virtual Appliance
Vulnerable Versions:
Unknown

Timeline

Official Publish: November 4th, 2021
Last Modified: November 7th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Weaknesses (CWE)

CWE-210

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.