Vulnerability identifier: #VU27597

Vulnerability risk: High

CVSSv3.1: 7.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-3196

CWE-ID: CWE-400

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Cisco Adaptive Security Appliance (ASA)
Hardware solutions / Security hardware applicances
Cisco Firepower Threat Defense (FTD)
Hardware solutions / Security hardware applicances

Vendor: Cisco Systems, Inc

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to application does not properly control consumption of internal resources in the Secure Sockets Layer (SSL)/Transport Layer Security (TLS) handler. A remote attacker can establish multiple SSL/TLS connections with specific conditions, trigger resource exhaustion and perform a denial of service (DoS) attack.

Mitigation
Vendor recommends to update the Cisco FTD Software Release to version 6.2.3.16 (June 2020), 6.3.0.6 (future release), 6.4.0.9 (May 2020) and 6.5.0.5 (future release).

Vulnerable software versions

Cisco Adaptive Security Appliance (ASA): 9.6 - 9.13

Cisco Firepower Threat Defense (FTD): 6.1.0, 6.2.2, 6.2.3, 6.3.0, 6.4.0, 6.5.0

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External links
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-ssl-vpn-dos-qY7BHpjN

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.