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CVE-2021-34749

Severity CVSS v4.0:
Pending analysis
Type:
CWE-200 Information Leak / Disclosure
Publication date:
18/08/2021
Last modified:
26/11/2024

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.

Impact

Vector 3.x
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N CVSS v3.1 Severity and Metrics:

Base Score: 5.80 MEDIUM
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Changed
Confidentiality (C): None
Integrity (I): Low
Availability (A): None

Base Score 3.x
5.80
Severity 3.x
MEDIUM
Vector 2.0
AV:N/AC:L/Au:N/C:N/I:P/A:N CVSS v2.0 Severity and Metrics:

Base Score: 5.00 MEDIUM
Vector: AV:N/AC:L/Au:N/C:N/I:P/A:N

Attack Vector (AV): Network
Attack Complexity (AC): Low
Authentication (Au): None
Confidentiality (C): None
Integrity (I): Physical
Availability (A): None

Base Score 2.0
5.00
Severity 2.0
MEDIUM

Vulnerable products and versions

CPE From Up to
cpe:2.3:a:cisco:ironport_web_security_appliance:14.5:*:*:*:*:*:*:*
cpe:2.3:a:cisco:secure_firewall_management_center:2.9.18:*:*:*:*:*:*:*
cpe:2.3:o:cisco:firepower_management_center_virtual_appliance_firmware:6.6.0:*:*:*:*:*:*:*
cpe:2.3:o:cisco:firepower_management_center_virtual_appliance_firmware:6.7.0:*:*:*:*:*:*:*
cpe:2.3:o:cisco:firepower_management_center_virtual_appliance_firmware:7.0.0:*:*:*:*:*:*:*
cpe:2.3:o:cisco:firepower_management_center_virtual_appliance_firmware:7.1.0:*:*:*:*:*:*:*

To consult the complete list of CPE names with products and versions, see this page


References to Advisories, Solutions, and Tools