Cisco Adaptive Security Appliance (ASA) Denial-of-Service Vulnerability
Cisco Adaptive Security Appliance (ASA) contains an improper input validation vulnerability with HTTP URLs. Exploitation could allow an attacker to cause a denial-of-service (DoS) condition or information disclosure.
A remote attacker, without authentication, can achieve partial data exposure, complete denial of service or system unavailability. Federal agencies are required to remediate by 2022-05-03 under CISA BOD 22-01.
This is a Improper Input Validation (CWE-20) vulnerability in Cisco Adaptive Security Appliance (ASA). A vulnerability in the web interface of the Cisco Adaptive Security Appliance (ASA) could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. It is also possible on certain software releases that the ASA will not reload, but an attacker could view sensitive system information without authentication by using directory traversal techniques. The vulnerability is due to lack of proper input validation of the HTTP URL. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. An exploit could allow the attacker to cause a DoS condition or unauthenticated disclosure of information. This vulnerability applies to IPv4 and IPv6 HTTP traffic. This vulnerability affects Cisco ASA Software and Cisco Firepower Threat Defense (FTD) Software that is running on the following Cisco products: 3000 Series Industrial Security Appliance (ISA), ASA 1000V Cloud Firewall, ASA 5500 Series Adaptive Security Appliances, ASA 5500-X Series Next-Generation Firewalls, ASA Services Module for Cisco Catalyst 6500 Series Switches and Cisco 7600 Series Routers, Adaptive Security Virtual Appliance (ASAv), Firepower 2100 Series Security Appliance, Firepower 4100 Series Security Appliance, Firepower 9300 ASA Security Module, FTD Virtual (FTDv). Cisco Bug IDs: CSCvi16029. Exploitation requires remote network access, low attack complexity, no authentication required, and no user interaction required.
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Phishing link
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Malicious file
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Server compromised
Probably yes if any of these apply:
Active exploitation documented in the wild. Threat-research write-up: http://packetstormsecurity.com/files/154017/Cisco-Adaptive-Security-Appliance-Path-Traversal.html
Manual remediation steps
Apply the Vendor Patch
This vulnerability is in the CISA Known Exploited Vulnerabilities catalog — apply the vendor's security update as soon as possible.
CISA required action: Apply updates per vendor instructions.
References
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References