CVE-2020-3561
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.
Published:Oct 21, 2020
Last Modified:Aug 11, 2026
EPS:Oct 21, 2020
EPSS Score:0.0128
CVSS Score:4.7
Affected Products
Vendor
Product
Action
Vendor
Cisco
Product
Adaptive Security Appliance
Cisco
Adaptive Security Appliance
Vendor
Cisco
Product
Adaptive Security Appliance Software
Cisco
Adaptive Security Appliance Software
Vendor
Cisco
Product
Secure Firewall Threat Defense
Cisco
Secure Firewall Threat Defense
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
Related CVEs
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
