CVE-2021-34749
Last modified
CVE-2021-34749 is a high-severity vulnerability rated 8.6/10 on the CVSS scale. 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. EPSS estimates a 1.68% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Ironport Web Security Appliance | 14.5 |
| Cisco | Secure Firewall Management Center | 2.9.18 |
| Cisco | Firepower Management Center Virtual Appliance Firmware | 6.6.0 |
| Cisco | Firepower Management Center Virtual Appliance Firmware | 6.7.0 |
| Cisco | Firepower Management Center Virtual Appliance Firmware | 7.0.0 |
| Cisco | Firepower Management Center Virtual Appliance Firmware | 7.1.0 |
References
Timeline
- Published
- Last Modified
- Status
- Modified
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