CVE-2021-34749 – Multiple Cisco Products Server Name Identification Data Exfiltration Vulnerability

https://notcve.org/view.php?id=CVE-2021-34749

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. Una vulnerabilidad en el filtrado de peticiones Server Name Identification (SNI) de Cisco Web Security Appliance (WSA), Cisco Firepower Threat Defense (FTD) y Snort detection engine podría permitir a un atacante no autenticado remoto omitir la tecnología de filtrado en un dispositivo afectado y exfiltrar datos de un host comprometido. • https://lists.debian.org/debian-lts-announce/2023/02/msg00011.html https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sni-data-exfil-mFgzXqLN https://www.debian.org/security/2023/dsa-5354 • CWE-200: Exposure of Sensitive Information to an Unauthorized Actor •