CVE-2026-20103
published 2026-03-04CVE-2026-20103: A vulnerability in the Remote Access SSL VPN functionality of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Secure Firewall Threat…
PriorityP353high8.6CVSS 3.1
AVNACLPRNUINSCCNINAH
EPSS
0.35%
27.3th percentile
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.
Affected
155 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| cisco | adaptive_security_appliance_software | >= 9.12.1 < 9.16.4.85 | 9.16.4.85 |
| cisco | adaptive_security_appliance_software | >= 9.17.1 < 9.18.4.66 | 9.18.4.66 |
| cisco | adaptive_security_appliance_software | >= 9.19.1 < 9.20.4 | 9.20.4 |
| cisco | adaptive_security_appliance_software | >= 9.22.1.1 < 9.22.2.4 | 9.22.2.4 |
| cisco | adaptive_security_appliance_software | >= 9.23.1 < 9.23.1.7 | 9.23.1.7 |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
CVSS provenance
nvdv3.18.6HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
vendor_cisco8.6HIGH
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Cisco
Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Remote Access SSL VPN Denial of Service Vulnerabilities
vendor_cisco·2026-03-05·CVSS 8.6
CVE-2026-20100 [HIGH] CWE-120 Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Remote Access SSL VPN Denial of Service Vulnerabilities
Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Remote Access SSL VPN Denial of Service Vulnerabilities
Multiple vulnerabilities in the Remote Access SSL VPN functionality of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow a remote attacker to cause an affected device to stop responding or to reload unexpectedly, resulting in a denial of service (DoS) condition that may require a manual reboot.
For more information about these vulnerabilities, see the Details section of this advisory.
Cisco has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities.
This advisory is available at the following l
Cisco
Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Remote Access SSL VPN Denial of Service Vulnerabilities
vendor_cisco·CVSS 3.1
CVE-2026-20103 Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Remote Access SSL VPN Denial of Service Vulnerabilities
CVE-2026-20103: Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Remote Access SSL VPN Denial of Service Vulnerabilities
Multiple vulnerabilities in the Remote Access SSL VPN functionality of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow a remote attacker to cause an affected device to stop responding or to reload unexpectedly, resulting in a denial of service (DoS) condition that may require a manual reboot. For more information about these vulnerabilities, see the
CVSS: 3.1
CWE: CWE-120, CWE-330, CWE-401, CWE-120, CWE-330, CWE-401, CWE-770, CWE-120, CWE-330, CWE-401, CWE-120, CWE-330, CWE-401, CWE-770
Bug IDs: CSCwo49932, CSCwo49934, CSCwo73886, CSCwo49932,
GHSA
GHSA-r8xj-9pfh-x4pw: A vulnerability in the Remote Access SSL VPN functionality of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Secure Firewall Thr
ghsa_unreviewed·2026-03-04
CVE-2026-20103 [HIGH] CWE-770 GHSA-r8xj-9pfh-x4pw: A vulnerability in the Remote Access SSL VPN functionality of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Secure Firewall Thr
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.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-03-04
Published