CVE detail

CVE-2021-1566 — CVE-2021-1566

Published 2021-06-16 · Modified 2026-06-17 · Vendor cisco · Product email_security_appliance · Source nvd
HIGH
severity
CVSS-derived band
7.4
CVSS v3
0–10 scale
0.0067
EPSS probability
exploitation probability, 30d
49.0%
EPSS percentile
percentile vs all CVEs
NOT LISTED
CISA KEV
known exploited catalog

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.

Remediation

ProductVulnerable rangeFixed versionAdvisory
Cisco Cisco Web Security Appliance (WSA)not specifiedadvisory ↗

References

cvedb.io · NVD · CISA KEV · FIRST EPSS · vendor advisories (CVE Program List v5). Informational only, no warranty — verify every remediation against the vendor advisory before acting on it. This product uses data from the NVD API but is not endorsed or certified by the NVD, CISA, FIRST.org or any vendor named. CVE® is a registered trademark of The MITRE Corporation.