Overview

A vulnerability has been identified in the WebVPN login page of Cisco Adaptive Security Appliance (ASA) Software. This security flaw could allow an unauthenticated, remote attacker to execute a cross-site scripting (XSS) attack against users accessing WebVPN on the Cisco ASA platform.

Technical Details

The vulnerability arises from insufficient input validation of a parameter within the WebVPN login page. Attackers can exploit this flaw by persuading a user to click on a malicious link, enabling them to inject and execute malicious scripts in the user’s browser.

Mitigation and Next Steps

Cisco urges customers to address this issue immediately by upgrading to a software version containing the necessary fixes. To obtain updated software, customers should contact their usual support channels. Note that free updates are not provided for vulnerabilities disclosed via Cisco Security Notices.

For further information on Cisco’s security policies and vulnerability management, please visit the Cisco Security Vulnerability Policy.

Customers Using Third-Party Support

If your Cisco products are managed through third-party organizations, such as Cisco Partners, authorized resellers, or service providers, consult your provider to ensure the fix or workaround is suitable for your network. Deploying an improper solution could lead to additional issues or incomplete remediation.

Recent Exploitation Activity

In November 2024, Cisco’s Product Security Incident Response Team (PSIRT) detected additional attempts to exploit this vulnerability in the wild. This development underscores the critical importance of upgrading to a fixed software version as soon as possible.

Conclusion

Cisco remains committed to assisting customers in safeguarding their networks. If you are affected by this vulnerability, take immediate action by consulting your support provider or upgrading to a secure software version.

Stay proactive to protect your systems and users from evolving threats. For updates and guidance, continue monitoring official Cisco channels.