Cisco Secure Firewall Threat Defense (Ftd) Software vulnerabilities

68 vulnerabilities

Known vulnerabilities in Cisco Secure Firewall Threat Defense (Ftd) Software, newest first, with CVSS severity, EPSS, KEV listings, ransomware use and the affected versions.

9.9CVE-2025-20333ciscoadaptive_security_appliance_software+3KEV
EPSS score
71.21%
A vulnerability in the VPN web server of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an authenticated, remote attacker to execute arbitrary code on an affected device. This vulnerability is due to improper validation of user-supplied input in HTTP(S) requests. An attacker with valid VPN user credentials could exploit this vulnerability by sending crafted HTTP requests to an affected device. A successful exploit could allow the attacker to execute arbitrary code as root, possibly resulting in the complete compromise of the affected device.5.8CVE-2025-20360ciscocisco cyber vision+1
EPSS score
0.38%
Multiple Cisco products are affected by a vulnerability in the Snort 3 HTTP Decoder that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart. This vulnerability is due to a lack of complete error checking when the MIME fields of the HTTP header are parsed. An attacker could exploit this vulnerability by sending crafted HTTP packets through an established connection to be parsed by Snort 3. A successful exploit could allow the attacker to cause a DoS condition when the Snort 3 Detection Engine unexpectedly restarts.9.1CVE-2025-20359ciscocisco cyber vision+3
EPSS score
0.48%
Multiple Cisco products are affected by a vulnerability in the Snort 3 HTTP Decoder that could allow an unauthenticated, remote attacker to cause the disclosure of possible sensitive data or cause the Snort 3 Detection Engine to crash. This vulnerability is due to an error in the logic of buffer handling when the MIME fields of the HTTP header are parsed. This can result in a buffer under-read. An attacker could exploit this vulnerability by sending crafted HTTP packets through an established connection that is parsed by Snort 3. A successful exploit could allow the attacker to induce one of two possible outcomes: the unexpected restarting of the Snort 3 Detection Engine, which could cause a denial of service (DoS) condition, or information disclosure of sensitive information in the Snort 3 data stream. Due to the under-read condition, it is possible that sensitive information that is not valid connection data could be returned.8.6CVE-2025-20362ciscoadaptive_security_appliance_software+3KEV
EPSS score
87.09%
Update: On November 5, 2025, Cisco became aware of a new attack variant against devices running Cisco Secure ASA Software or Cisco Secure FTD Software releases that are affected by CVE-2025-20333 and CVE-2025-20362. This attack can cause unpatched devices to unexpectedly reload, leading to denial of service (DoS) conditions. Cisco strongly recommends that all customers upgrade to the fixed software releases that are listed in the Fixed Software ["#fs"] section of this advisory. A vulnerability in the VPN web server of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to access restricted URL endpoints that are related to remote access VPN that should otherwise be inaccessible without authentication. This vulnerability is due to improper validation of user-supplied input in HTTP(S) requests. An attacker could exploit this vulnerability by sending crafted HTTP requests to a targeted web server on a device. A successful exploit could allow the attacker to access a restricted URL without authentication.8.6CVE-2024-20260ciscocisco secure firewall adaptive security appliance (asa) software+1
EPSS score
0.59%
Update for September 16, 2026: The original 1.0 version of this advisory was specific to the Cisco Adaptive Security Virtual Appliance (ASAv) and Cisco Secure Firewall Threat Defense Virtual (FTDv) models. However, it was later found that this vulnerability affects all Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software platforms. A vulnerability in the VPN and management web servers of the Cisco Secure Firewall ASA Software and Cisco Secure FTD Software platforms could allow an unauthenticated, remote attacker to cause an affected device to run out of system memory or buffer blocks, which in turn could cause SSL VPN connection processing to slow down and eventually cease altogether. This vulnerability is due to a lack of proper memory management for new incoming SSL/TLS connections. An attacker could exploit this vulnerability by sending a large number of new incoming SSL/TLS connections to the targeted device. A successful exploit could allow the attacker to deplete system memory or buffers, resulting in a denial of service (DoS) condition. The memory or buffers could be reclaimed slowly if the attack traffic is stopped, but a manual reload may be required to restore operations quickly.6.7CVE-2024-20358ciscoadaptive_security_appliance_software+3
EPSS score
0.70%
A vulnerability in the Cisco Adaptive Security Appliance (ASA) restore functionality that is available in Cisco ASA Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, local attacker to execute arbitrary commands on the underlying operating system with root-level privileges. Administrator-level privileges are required to exploit this vulnerability. This vulnerability exists because the contents of a backup file are improperly sanitized at restore time. An attacker could exploit this vulnerability by restoring a crafted backup file to an affected device. A successful exploit could allow the attacker to execute arbitrary commands on the underlying Linux operating system as root.5.8CVE-2026-20066ciscocisco secure firewall threat defense (ftd) software+4
EPSS score
0.47%
Multiple Cisco products are affected by a vulnerability in the Snort 3 Detection Engine that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart, resulting in an interruption of packet inspection. This vulnerability is due to an error in the JSTokenizer normalization logic when the HTTP inspection normalizes JavaScript. An attacker could exploit this vulnerability by sending crafted HTTP packets through an established connection that is parsed by Snort 3. A successful exploit could allow the attacker to cause a DoS condition when the Snort 3 Detection Engine restarts unexpectedly. JSTokenizer is not enabled by default.8.3CVE-2026-20323ciscocisco secure firewall management center (fmc)+1
EPSS score
0.09%
A vulnerability in the sftunnel inter-device communication protocol of Cisco Secure FMC Software and Cisco Secure FTD Software could allow an unauthenticated, adjacent attacker to impersonate the peer device and obtain access at the level of the manager role, which is equivalent to root. This vulnerability is due to improper management of the TLS certificate for the sftunnel management connection. An attacker could exploit this vulnerability by connecting to the sftunnel port using a crafted TLS certificate. A successful exploit could allow the attacker to become a registered sftunnel peer with root access. Note: The attack is successful only if the sftunnel connection is down or the attack can disrupt the sftunnel connection long enough to execute the attack.7.7CVE-2026-20100ciscoadaptive_security_appliance_software+3
EPSS score
0.29%
A vulnerability in the LUA interperter of the Remote Access SSL VPN feature of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Secure Firewall Threat Defense (FTD) Software could allow an authenticated, remote attacker with a valid VPN connection to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. This does not affect the management or MUS interfaces. This vulnerability is due to trusting user input without validation in the LUA interprerter. An attacker could exploit this vulnerability by sending crafted HTTP packets to the Remote Access SSL VPN server. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.6.5CVE-2026-20022ciscoadaptive_security_appliance_software+3
EPSS score
0.20%
A vulnerability in the OSPF protocol of Cisco Secure Firewall ASA Software and Cisco Secure FTD Software could allow an unauthenticated, adjacent attacker to cause an affected device to reload unexpectedly, resulting in a DoS condition when OSPF canonicalization debug is enabled by using the command debug ip ospf canon. This vulnerability is due to insufficient input validation when processing OSPF LSU packets. An attacker could exploit this vulnerability by sending crafted unauthenticated OSPF packets. A successful exploit could allow the attacker to write to memory outside of the packet data, causing the device to reload, resulting in a DoS condition.8.6CVE-2026-20135ciscocisco secure firewall threat defense (ftd) software
EPSS score
0.46%
A vulnerability in the TLS 1.3 implementation in Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to improper buffer management during the TLS 1.3 connection. An attacker could exploit this vulnerability by sending a crafted TLS 1.3 packet to an affected system through a TLS 1.3-enabled listening socket. A successful exploit could allow the attacker to cause the LINA process to crash, which would cause the device to reload. The reload can happen before or after authentication of the connection.Note: TLS 1.3 connections include both data traffic and user-management traffic.6CVE-2026-20008ciscoadaptive_security_appliance_software+3
EPSS score
0.14%
A vulnerability in a small subset of CLI commands that are used on Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an authenticated, local attacker to craft Lua code that could be used on the underlying operating system as root. This vulnerability exists because user-provided input is not properly sanitized. An attacker could exploit this vulnerability by crafting valid Lua code and submitting it as a malicious parameter for a CLI command. A successful exploit could allow the attacker to inject Lua code, which could lead to arbitrary code execution as the root user. To exploit this vulnerability, an attacker must have valid Administrator credentials.5.8CVE-2026-20005ciscocisco cyber vision+6
EPSS score
0.51%
Multiple Cisco products are affected by a vulnerability in the Snort 3 Detection Engine that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart, resulting in an interruption of packet inspection. This vulnerability is due to incomplete parsing of the SSL handshake ingress packets. An attacker could exploit this vulnerability by sending crafted SSL handshake packets. A successful exploit could allow the attacker to cause a denial of service (DoS) condition when the Snort 3 Detection Engine restarts unexpectedly.8.1CVE-2026-20335ciscocisco secure firewall adaptive security appliance (asa) software+2
EPSS score
0.28%
As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Secure Adaptive Security Appliance Software, Cisco Secure Firewall Threat Defense Software and Cisco Secure Firewall Management Center Software engineering team has conducted a comprehensive internal security review. This review resulted in a software hardening release that addresses multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-20335 are related to incorrect calculation issues that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-682.5.8CVE-2026-20013ciscoadaptive_security_appliance_software+3
EPSS score
0.31%
A vulnerability in the IKEv2 feature of Cisco Secure Firewall ASA Software and Cisco Secure FTD Software could allow an unauthenticated, remote attacker to cause a DoS condition on an affected device that may also impact the availability of services to devices elsewhere in the network. This vulnerability is due to memory exhaustion caused by not freeing memory during IKEv2 packet processing. An attacker could exploit this vulnerability by sending crafted IKEv2 packets to an affected device. A successful exploit could allow the attacker to exhaust resources, causing a DoS condition that will eventually require the device to manually reload.8.6CVE-2026-20249ciscocisco secure firewall adaptive security appliance (asa) software+1
EPSS score
0.40%
A vulnerability in the certification authentication feature of Internet Key Exchange version 2 (IKEv2) for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly. This vulnerability is due to a logic error during the certificate authentication phase of the IKEv2 connection setup. An attacker could exploit this vulnerability by attempting to establish an IKEv2 VPN connection with a crafted certificate. A successful exploit could allow the attacker to cause the IKEv2 process to crash, causing a denial of service (DoS) condition.5.8CVE-2026-20054ciscocisco cyber vision+6
EPSS score
0.45%
Multiple Cisco products are affected by a vulnerability in the Snort 3 VBA feature that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to crash.  This vulnerability is due to improper error checking when decompressing VBA data. An attacker could exploit this vulnerability by sending crafted VBA data to the Snort 3 Detection Engine on the targeted device. A successful exploit could allow the attacker to cause the Snort 3 Detection Engine to enter an infinite loop, causing a DoS condition.5.8CVE-2026-20007ciscocisco secure firewall threat defense (ftd) software+1
EPSS score
0.24%
A vulnerability in the Snort 2 and Snort 3 deep packet inspection of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured Snort rules and allow traffic onto the network that should have been dropped. This vulnerability is due to a logic error in the integration of the Snort Engine rules with Cisco Secure FTD Software that could allow different Snort rules to be hit when deep inspection of the packet is performed for the inner and outer connections. An attacker could exploit this vulnerability by sending crafted traffic to a targeted device that would hit configured Snort rules. A successful exploit could allow the attacker to send traffic to a network where it should have been denied.8.8CVE-2026-20336ciscocisco secure firewall adaptive security appliance (asa) software+2
EPSS score
0.20%
As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Secure Adaptive Security Appliance Software, Cisco Secure Firewall Threat Defense Software and Cisco Secure Firewall Management Center Software engineering team has conducted a comprehensive internal security review. This review resulted in a software hardening release that addresses multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-20336 are related to issues concerning improper control of a resource through its lifetime that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-664.5.3CVE-2026-20106ciscoadaptive_security_appliance_software+3
EPSS score
0.33%
A vulnerability in the Remote Access SSL VPN, HTTP management and MUS 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 requiring a manual reboot. 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 to stop responding, resulting in a DoS condition.