CVE-2021-1566 - CVE House
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Status published High CVE-2021-1566

Cisco Email Security Appliance and Cisco Web Security Appliance Certificate Validation Vulnerability

Vulnerability Description

A vulnerability in the Cisco Advanced Malware Protection (AMP) for Endpoints integration of Cisco AsyncOS for Cisco Email Security Appliance (ESA) and Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to intercept traffic between an affected device and the AMP servers. This vulnerability is due to improper certificate validation when an affected device establishes TLS connections. A man-in-the-middle attacker could exploit this vulnerability by sending a crafted TLS packet to an affected device. A successful exploit could allow the attacker to spoof a trusted host and then extract sensitive information or alter certain API requests.

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 Web Security Appliance (WSA)
Vulnerable Versions:
Unknown

Timeline

Official Publish: June 16th, 2021
Last Modified: November 7th, 2024
Added to House: July 21st, 2026

CVSS Vectors

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

Weaknesses (CWE)

CWE-296

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.