CVE ID:	CVE-2021-34749
Description:	A vulnerability in Server Name Identification (SNI) request filtering of Cisco Web Security Appliance (WSA), Cisco Firepower Threat Defense (FTD), and the Snort detection engine could allow an unauthenticated, remote attacker to bypass filtering technology on an affected device and exfiltrate data from a compromised host. This vulnerability is due to inadequate filtering of the SSL handshake. An attacker could exploit this vulnerability by using data from the SSL client hello packet to communicate with an external server. A successful exploit could allow the attacker to execute a command-and-control attack on a compromised host and perform additional data exfiltration attacks.
Test IDs:	None available
Cross References:	Common Vulnerability Exposure (CVE) ID: CVE-2021-34749 Cisco Security Advisory: 20210818 Multiple Cisco Products Server Name Identification Data Exfiltration Vulnerability https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sni-data-exfil-mFgzXqLN Debian Security Information: DSA-5354 (Google Search) https://www.debian.org/security/2023/dsa-5354 https://lists.debian.org/debian-lts-announce/2023/02/msg00011.html