Cisco Secure Firewall Adaptive Security Appliance (ASA) Software vulnerabilities
27 known vulnerabilities in Cisco Secure Firewall Adaptive Security Appliance (ASA) Software from Cisco. 27 are rated high or critical, and 4 have been exploited in real attacks. Each entry lists the affected versions and the release that fixes it, where the vendor has published one.
Latest first
- 8.6 High severity
Cisco Secure Firewall ASA Software and Cisco Secure FTD Software Unchecked Return Value to NULL Pointer Dereference Exploited
A vulnerability in the Remote Access SSL VPN service of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to reload unexp
- 8.8 High severity
Cisco Secure Firewall Adaptive Security…: Improper Control of a Resource Through its Lifetime
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 cond
- 8.1 High severity
Cisco Secure Firewall Adaptive Security…: Incorrect Calculation
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 cond
- 8.4 High severity
Cisco Secure Firewall Adaptive Security…: Improper Adherence to Coding Standards
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 cond
- 8.8 High severity
Cisco Secure Firewall Adaptive Security…: Incorrect Comparison
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 cond
- 9.9 Critical severity
Cisco Secure Firewall Adaptive Security…: Improper Access Control
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 cond
- 8.6 High severity
Cisco Secure Firewall Adaptive Security…: Missing Release of Resource after Effective Lifetime
A vulnerability in Datagram TLS (DTLS) message handling of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software for Cisco Secure Firewall 3100 Series and 4200 Series devices could allow an una
- 8.6 High severity
Cisco Secure Firewall Adaptive Security…: Incorrect Type Conversion or Cast
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 unauthentica
- 7.4 High severity
Cisco Secure Firewall Adaptive Security…: Missing Release of Memory after Effective Lifetime
A vulnerability in the EIGRP implementation in Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, adjacent attacker to cause the device to reload unexpectedly
- 8.6 High severity
Cisco Secure Firewall Adaptive Security…: Loop with Unreachable Exit Condition
A vulnerability in the system rate-limiting process for syslog message 419002 of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause h
- 9.9 Critical severity
Cisco Secure Firewall Adaptive Security…: Improper Neutralization
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 cond
- 9.9 Critical severity
Cisco Secure Firewall Adaptive Security…: Improper Check or Handling of Exceptional Conditions
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 cond
- 9.6 Critical severity
Cisco Secure Firewall Adaptive Security…: Protection Mechanism Failure
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 cond
- 8.6 High severity
Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) Heap Inspection Exploited
A vulnerability in the Remote Access SSL VPN service 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 the device to reload unex
- 8.6 High severity
IOS: Missing Release of Memory after Effective Lifetime
A vulnerability in the Internet Key Exchange version 2 (IKEv2) feature of Cisco IOS Software, Cisco IOS XE Software, Cisco Secure Firewall Adaptive Security Appliance (ASA) Software, and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauth
- 7.7 High severity
Cisco Secure Firewall Adaptive Security…: Missing Release of Memory after Effective Lifetime
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 authenticated, remote attacker with a valid VPN connection to exhaus
- 8.6 High severity
Cisco Secure Firewall Adaptive Security…: Allocation of Resources Without Limits or Throttling
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
- 8.6 High severity
Cisco Secure Firewall Adaptive Security…: Use of Insufficiently Random Values
A vulnerability in the SAML 2.0 single sign-on (SSO) feature of Cisco Secure Firewall ASA Software and Secure FTD Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a DoS condition. This vulnerabil
- 7.7 High severity
Cisco Secure Firewall Adaptive Security…: Buffer Copy without Checking Size of Input
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 con
- 8.6 High severity
Cisco Secure Firewall Adaptive Security…: Missing Release of Resource after Effective Lifetime
A vulnerability in the handling of the embryonic connection limits in Cisco Secure Firewall Adaptive Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to cause incoming TCP SYN packets to be dropped incorrectly. This vulnerabili
- 7.2 High severity
Cisco Secure Firewall Adaptive Security…: Incorrect Execution-Assigned Permissions
A vulnerability in the CLI of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software in multiple context mode could allow an authenticated, local attacker with administrative privileges in one context to copy files to or from another context, includi
- 7.7 High severity
Cisco Secure Firewall Adaptive Security…: Incorrect Calculation of Buffer Size
A vulnerability in the processing of Galois/Counter Mode (GCM)-encrypted Internet Key Exchange version 2 (IKEv2) IPsec traffic of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could all
- 8.6 High severity
Cisco Secure Firewall Adaptive Security…: Improper Clearing of Heap Memory Before Release
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 cause a denial of service (DoS) condition on an
- 7.7 High severity
Cisco Secure Firewall Adaptive Security…: Missing Release of Memory after Effective Lifetime
A vulnerability in the IKEv2 feature of Cisco Secure Firewall ASA Software and Cisco Secure FTD Software could allow an authenticated, remote attacker with valid VPN user credentials to cause a DoS condition on an affected device that may also impact the avail
- 8.6 High severity
Cisco Secure Firewall Adaptive Security (ASA) Appliance and Secure Firewall Threat Defense (FTD) Missing Authorization Exploited
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 u
- 9.9 Critical severity
Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) Buffer Overflow Exploited
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. Thi
- 8.6 High severity
Cisco Secure Firewall Adaptive Security…: Memory Allocation with Excessive Size Value
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 af