CVE-2018-0296 remediation guide
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 af...
Identify the affected asset
Confirm whether Cisco Adaptive Security Appliance (ASA) is installed, record the deployed version and installation path, and identify exposed interfaces.
- Record the product name, package or appliance identifier, and installed version.
- Identify internet-facing, administrative, API, and internal access paths.
- Preserve the pre-change configuration and relevant service logs.
Validate the affected-version match
Compare the deployed version with the affected range: Cisco Adaptive Security Appliance unknown, >= 9.1 < 9.1.7.29, >= 9.2 < 9.2.4.33, >= 9.3 < 9.4.4.18, >= 9.5 < 9.6.4.8, >= 9.7 < 9.7.1.24, >= 9.8 < 9.8.2.28, >= 9.9 < 9.9.2.1, >= 6.0 < 6.1.0, >= 6.2.1 < 6.2.2.3, 6.2.3, 6.2.3-85.02, 6.2.3-851, 6.2.3.1. Treat incomplete inventory results as unresolved.
Prioritize with independent signals
CISA has listed this vulnerability in the Known Exploited Vulnerabilities catalog. Combine this signal with asset criticality, exposure, compensating controls, and business impact.
Apply supported remediation
Apply updates per vendor instructions.
Verify the result
Confirm the resulting version, service health, authentication and access paths, monitoring coverage, and relevant security logs.
- Confirm the expected version and package state.
- Run a functional health check for critical service paths.
- Review authentication, error, application, and security monitoring logs.
- Reassess exposure if the supported fix cannot be applied.
Operational boundary
This page does not replace the vendor advisory, support contract, change-management process, or recovery plan. Do not infer that an asset is unaffected from an incomplete inventory query or a missing fixed-version field.