CRLF injection in Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software

1) CRLF injection

EUVDB-ID: #VU47886

Risk: Medium

CVSSv4.0: 1.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-3561

CWE-ID: CWE-93 - Improper Neutralization of CRLF Sequences ('CRLF Injection')

Exploit availability: No

Description

The vulnerability allows a remote attacker to inject arbitrary data in server response.

The vulnerability exists due to insufficient validation of attacker-supplied data in the Clientless SSL VPN (WebVPN). A remote attacker can trick a victim to click a specially crafted link and redirect the user to arbitrary websites.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Cisco Adaptive Security Appliance (ASA): - - 9.14

Cisco Firepower Threat Defense (FTD): - - 6.6.0

CPE2.3

• cpe:2.3:h:cisco_systems:asa:*:*:*:*:*:*:*:*
• cpe:2.3:h:cisco_systems:asa:9.6:*:*:*:*:*:*:*
• cpe:2.3:h:cisco_systems:asa:9.7:*:*:*:*:*:*:*
• cpe:2.3:h:cisco_systems:asa:9.8:*:*:*:*:*:*:*
• cpe:2.3:h:cisco_systems:asa:9.9:*:*:*:*:*:*:*
• cpe:2.3:h:cisco_systems:asa:9.10:*:*:*:*:*:*:*
• cpe:2.3:h:cisco_systems:asa:9.12:*:*:*:*:*:*:*
• cpe:2.3:h:cisco_systems:asa:9.13:*:*:*:*:*:*:*
• cpe:2.3:h:cisco_systems:asa:9.14:*:*:*:*:*:*:*
• cpe:2.3:h:cisco_systems:cisco_ftd:*:*:*:*:*:*:*:*

External links

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-ftd-crlf-inj-BX9uRwSn

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.