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.
| Software | From | Fixed in |
|---|---|---|
| cisco / adaptive_security_appliance_software | 9.1 | 9.1.7.29 |
| cisco / adaptive_security_appliance_software | 9.2 | 9.2.4.33 |
| cisco / adaptive_security_appliance_software | 9.3 | 9.4.4.18 |
| cisco / adaptive_security_appliance_software | 9.5 | 9.6.4.8 |
| cisco / adaptive_security_appliance_software | 9.7 | 9.7.1.24 |
| cisco / adaptive_security_appliance_software | 9.8 | 9.8.2.28 |
| cisco / adaptive_security_appliance_software | 9.9 | 9.9.2.1 |
| cisco / firepower_threat_defense | 6.2.3 | 6.2.3.x |
| cisco / firepower_threat_defense | 6.0 | 6.1.0 |
| cisco / firepower_threat_defense | 6.2.1 | 6.2.2.3 |
| cisco / firepower_threat_defense | 6.2.3.1 | 6.2.3.1.x |
| cisco / firepower_threat_defense | 6.2.3-851 | 6.2.3-851.x |
| cisco / firepower_threat_defense | 6.2.3-85.02 | 6.2.3-85.02.x |
A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.
CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.
A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.
Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.
Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.
SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.