CVE-2020-3561: Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software WebVPN CRLF Injection Vulnerability

Published Oct 21, 2020
·
Updated

A vulnerability in the Clientless SSL VPN (WebVPN) of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to inject arbitrary HTTP headers in the responses of the affected system. The vulnerability is due to improper input sanitization. An attacker could exploit this vulnerability by persuading a user of the interface to click a crafted link. A successful exploit could allow the attacker to conduct a CRLF injection attack, adding arbitrary HTTP headers in the responses of the system and redirecting the user to arbitrary websites.

Affected Software

15 affected components
Cisco Adaptive Security Appliance<9.6.4.35
Cisco Firepower Threat Defense<6.3.0.6
Cisco Firepower Threat Defense>=6.4.0<6.4.0.10
Cisco Firepower Threat Defense>=6.5.0<6.5.0.5
Cisco Firepower Threat Defense>=6.6.0<6.6.1
Cisco Adaptive Security Appliance Software>=9.8.0<9.8.4.20
Cisco Adaptive Security Appliance Software>=9.9.0<9.9.2.80
Cisco Adaptive Security Appliance Software>=9.10.0<9.10.1.43
Cisco Adaptive Security Appliance Software>=9.12.0<9.12.3.9
Cisco Adaptive Security Appliance Software>=9.13.0<9.13.1.10
Cisco Adaptive Security Appliance Software>=9.14.0<9.14.1.10
Cisco Secure Firewall Threat Defense<6.3.0.6
Cisco Secure Firewall Threat Defense>=6.4.0<6.4.0.10
Cisco Secure Firewall Threat Defense>=6.5.0<6.5.0.5
Cisco Secure Firewall Threat Defense>=6.6.0<6.6.1

Event History

Oct 21, 2020
CVE Published
via MITRE·06:41 PM
Data Sourced
via MITRE·06:41 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·07:15 PM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is the vulnerability ID?

The vulnerability ID is CVE-2020-3561.

2

What is the severity of CVE-2020-3561?

The severity of CVE-2020-3561 is medium with a CVSS score of 4.7.

3

What is the affected software?

The affected software includes Cisco Adaptive Security Appliance (ASA) Software versions up to 9.6.4.35 and Cisco Firepower Threat Defense (FTD) Software versions up to 6.3.0.6.

4

How can an attacker exploit this vulnerability?

An unauthenticated, remote attacker can exploit this vulnerability by injecting arbitrary HTTP headers in the responses of the affected system.

5

Is there a fix for CVE-2020-3561?

Yes, Cisco has released software updates to address this vulnerability. Please refer to the Cisco Security Advisory for more information.

Contact

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