| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| A vulnerability in the remote access VPN feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to conduct a brute force attack in an attempt to identify valid username and password combinations or an authenticated, remote attacker to establish a clientless SSL VPN session with an unauthorized user.
This vulnerability is due to improper separation of authentication, authorization, and accounting (AAA) between the remote access VPN feature and the HTTPS management and site-to-site VPN features. An attacker could exploit this vulnerability by specifying a default connection profile/tunnel group while conducting a brute force attack or while establishing a clientless SSL VPN session using valid credentials. A successful exploit could allow the attacker to achieve one or both of the following:
Identify valid credentials that could then be used to establish an unauthorized remote access VPN session.
Establish a clientless SSL VPN session (only when running Cisco ASA Software Release 9.16 or earlier).
Notes:
Establishing a client-based remote access VPN tunnel is not possible as these default connection profiles/tunnel groups do not and cannot have an IP address pool configured.
This vulnerability does not allow an attacker to bypass authentication. To successfully establish a remote access VPN session, valid credentials are required, including a valid second factor if multi-factor authentication (MFA) is configured.
Cisco will release software updates that address this vulnerability. There are workarounds that address this vulnerability. |
| Multiple vulnerabilities in the payload inspection for Ethernet Industrial Protocol (ENIP) traffic for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured rules for ENIP traffic. These vulnerabilities are due to incomplete processing during deep packet inspection for ENIP packets. An attacker could exploit these vulnerabilities by sending a crafted ENIP packet to the targeted interface. A successful exploit could allow the attacker to bypass configured access control and intrusion policies that should be activated for the ENIP packet. |
| A vulnerability in the processing of SSH connections for multi-instance deployments of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on the affected device. This vulnerability is due to a lack of proper error handling when an SSH session fails to be established. An attacker could exploit this vulnerability by sending a high rate of crafted SSH connections to the instance. A successful exploit could allow the attacker to cause resource exhaustion, which causes a DoS condition on the affected device. The device must be manually reloaded to recover. |
| A vulnerability in the software-based SSL/TLS message handler of Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. This vulnerability is due to insufficient validation of SSL/TLS messages when the device performs software-based SSL/TLS decryption. An attacker could exploit this vulnerability by sending a crafted SSL/TLS message to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Note: Datagram TLS (DTLS) messages cannot be used to exploit this vulnerability. |
| A vulnerability in the memory management of Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper resource management when connection rates are high. An attacker could exploit this vulnerability by opening a significant number of connections on an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition. |
| A vulnerability in the Simple Network Management Protocol version 3 (SNMPv3) access control functionality of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to query SNMP data. This vulnerability is due to ineffective access control. An attacker could exploit this vulnerability by sending an SNMPv3 query to an affected device from a host that is not permitted by the SNMPv3 access control list. A successful exploit could allow the attacker to send an SNMP query to an affected device and retrieve information from the device. The attacker would need valid credentials to perform the SNMP query. |
| Multiple Cisco products are affected by a vulnerability in Snort rules that could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.The vulnerability is due to improper handling of the Block with Reset or Interactive Block with Reset actions if a rule is configured without proper constraints. An attacker could exploit this vulnerability by sending a crafted IP packet to the affected device. A successful exploit could allow the attacker to cause through traffic to be dropped. Note: Only products with Snort3 configured and either a rule with Block with Reset or Interactive Block with Reset actions configured are vulnerable. Products configured with Snort2 are not vulnerable. |
| 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. |
| A vulnerability in the web services of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software, Cisco Secure Firewall Threat Defense (FTD) Software, Cisco IOS Software, Cisco IOS XE Software, and Cisco IOS XR Software could allow an unauthenticated, remote attacker (Cisco ASA and FTD Software) or authenticated, remote attacker (Cisco IOS, IOS XE, and IOS XR Software) with low user privileges to execute arbitrary code on an affected device.
This vulnerability is due to improper validation of user-supplied input in HTTP requests. An attacker could exploit this vulnerability by sending crafted HTTP requests to a targeted web service on an affected device after obtaining additional information about the system, overcoming exploit mitigations, or both. A successful exploit could allow the attacker to execute arbitrary code as root, which may lead to the complete compromise of the affected device.
For more information about this vulnerability, see the Details ["#details"] section of this advisory. |
| 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. If OSPF authentication is enabled, the attacker must know the secret key to exploit this vulnerability.
This vulnerability is due to insufficient input validation when processing OSPF update packets. An attacker could exploit this vulnerability by sending crafted OSPF update packets. A successful exploit could allow the attacker to create a buffer overflow, causing the affected device to reload, resulting in a DoS condition. |
| 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. |
| A vulnerability in the VPN web client services component of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to conduct browser-based attacks against users of an affected device. This vulnerability is due to improper validation of input that is passed to the VPN web client services component before being returned to the browser that is in use. An attacker could exploit this vulnerability by persuading a user to visit a website that is designed to pass malicious requests to a device that is running Cisco ASA Software or Cisco FTD Software and has web services endpoints supporting VPN features enabled. A successful exploit could allow the attacker to reflect malicious input from the affected device to the browser that is in use and conduct browser-based attacks, including cross-site scripting attacks. The attacker could not directly impact the affected device. |
| A vulnerability in the handling of RSA keys on devices running Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to retrieve an RSA private key. This vulnerability is due to a logic error when the RSA key is stored in memory on a hardware platform that performs hardware-based cryptography. An attacker could exploit this vulnerability by using a Lenstra side-channel attack against the targeted device. A successful exploit could allow the attacker to retrieve the RSA private key. The following conditions may be observed on an affected device: This vulnerability will apply to approximately 5 percent of the RSA keys on a device that is running a vulnerable release of Cisco ASA Software or Cisco FTD Software; not all RSA keys are expected to be affected due to mathematical calculations applied to the RSA key. The RSA key could be valid but have specific characteristics that make it vulnerable to the potential leak of the RSA private key. If an attacker obtains the RSA private key, they could use the key to impersonate a device that is running Cisco ASA Software or Cisco FTD Software or to decrypt the device traffic. See the Indicators of Compromise section for more information on the detection of this type of RSA key. The RSA key could be malformed and invalid. A malformed RSA key is not functional, and a TLS client connection to a device that is running Cisco ASA Software or Cisco FTD Software that uses the malformed RSA key will result in a TLS signature failure, which means a vulnerable software release created an invalid RSA signature that failed verification. If an attacker obtains the RSA private key, they could use the key to impersonate a device that is running Cisco ASA Software or Cisco FTD Software or to decrypt the device traffic. |
| A vulnerability in CLI command processing in the Cisco Firepower 4100 Series Next-Generation Firewall and Cisco Firepower 9300 Security Appliance could allow an authenticated, local attacker to inject arbitrary shell commands that are executed by the device. More Information: CSCvb61343. Known Affected Releases: 2.0(1.68). Known Fixed Releases: 2.0(1.118) 2.1(1.47) 92.1(1.1646) 92.1(1.1763) 92.2(1.101). |
| A vulnerability in the detection engine that handles Secure Sockets Layer (SSL) packets for Cisco Firepower System Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition because the Snort process unexpectedly restarts. This vulnerability affects Cisco Firepower System Software prior to the first fixed release when it is configured with an SSL Decrypt-Resign policy. More Information: CSCvb62292. Known Affected Releases: 6.0.1 6.1.0 6.2.0. Known Fixed Releases: 6.2.0 6.1.0.2. |
| A vulnerability in the activation of an access control list (ACL) on Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass the protection that is offered by a configured ACL on an affected device. This vulnerability is due to a logic error that occurs when an ACL changes from inactive to active in the running configuration of an affected device. An attacker could exploit this vulnerability by sending traffic through the affected device that should be denied by the configured ACL. The reverse condition is also true—traffic that should be permitted could be denied by the configured ACL. A successful exploit could allow the attacker to bypass configured ACL protections on the affected device, allowing the attacker to access trusted networks that the device might be protecting. Note: This vulnerability applies to both IPv4 and IPv6 traffic as well as dual-stack ACL configurations in which both IPv4 and IPv6 ACLs are configured on an interface. |
| A "Cisco Firepower Threat Defense 6.0.0 through 6.2.2 and Cisco ASA with FirePOWER Module Denial of Service" vulnerability in the access control policy of Cisco Firepower System Software could allow an authenticated, remote attacker to cause an affected system to stop inspecting and processing packets, resulting in a denial of service (DoS) condition. The vulnerability is due to improper SSL policy handling by the affected software when packets are passed through the sensing interfaces of an affected system. An attacker could exploit this vulnerability by sending crafted packets through a targeted system. This vulnerability affects Cisco Firepower System Software that is configured with the SSL policy feature. Cisco Bug IDs: CSCvc84361. |
| A vulnerability in the logging configuration of Secure Sockets Layer (SSL) policies for Cisco FirePOWER System Software 5.3.0 through 6.2.2 could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition due to high consumption of system resources. The vulnerability is due to the logging of certain TCP packets by the affected software. An attacker could exploit this vulnerability by sending a flood of crafted TCP packets to an affected device. A successful exploit could allow the attacker to cause a DoS condition. The success of an exploit is dependent on how an administrator has configured logging for SSL policies for a device. This vulnerability affects Cisco FirePOWER System Software that is configured to log connections by using SSL policy default actions. Cisco Bug IDs: CSCvd07072. |
| A vulnerability in the detection engine of Cisco Firepower Threat Defense software could allow an unauthenticated, remote attacker to bypass a configured Secure Sockets Layer (SSL) Access Control (AC) policy to block SSL traffic. The vulnerability is due to the incorrect handling of TCP SSL packets received out of order. An attacker could exploit this vulnerability by sending a crafted SSL connection through the affected device. A successful exploit could allow the attacker to bypass a configured SSL AC policy to block SSL traffic. Cisco Bug IDs: CSCvg09316. |
| A vulnerability in the secure boot implementation of Cisco Secure Firewalls 3100 Series that are running Cisco Adaptive Security Appliance (ASA) Software or Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated attacker with physical access to the device to bypass the secure boot functionality.
This vulnerability is due to a logic error in the boot process. An attacker could exploit this vulnerability by injecting malicious code into a specific memory location during the boot process of an affected device. A successful exploit could allow the attacker to execute persistent code at boot time and break the chain of trust. |
