CVE-2026-20103
HIGHCVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
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2Tags
Description
A vulnerability in the Remote Access SSL VPN functionality of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to exhaust device memory resulting in a denial of service (DoS) condition to new Remote Access SSL VPN connections. This does not affect the management interface, though it may become temporarily unresponsive. This vulnerability is due to trusting user input without validation. An attacker could exploit this vulnerability by sending crafted packets to the Remote Access SSL VPN server. A successful exploit could allow the attacker to cause the device web interface to stop responding, resulting in a DoS condition.
Analysis
Denial of service in Cisco Secure Firewall ASA and FTD Remote Access SSL VPN allows unauthenticated remote attackers to exhaust device memory through malformed packets, causing the VPN service to become unresponsive. The vulnerability stems from insufficient input validation on the SSL VPN server and currently has no available patch. …
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Remediation
Within 24 hours: Inventory all Cisco ASA and FTD devices running SSL VPN and assess business criticality of each. Within 7 days: Implement network segmentation to restrict SSL VPN access to known IP ranges and enable connection rate limiting on VPN gateways. …
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