Cisco

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco IOS XE Software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities.   

These vulnerabilities were found during internal testing and are not known to be actively exploited. To assist customers in patching and streamline the disclosure process, Cisco has grouped these issues by their underlying vulnerability class — Common Weakness Enumeration (CWE) — and assigned a single Common Vulnerabilities and Exposures identifier (CVE ID).

Cisco has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities.

This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-iosxe-V8NMuMZJ

<br/>Security Impact Rating: Critical <br/>CVE: CVE-2026-20267,CVE-2026-20268,CVE-2026-20269,CVE-2026-20270,CVE-2026-20271,CVE-2026-20272,CVE-2026-20273

On October 7, 2026, the Cisco Product Security Incident Response Team (PSIRT) will publish advisories to disclose security vulnerability information along with fixed software releases for the following Cisco products:

• Application Policy Infrastructure Controller (security hardening release)
• Finesse
• License On-Prem, formerly Cisco Smart Software Manager On-Prem (security hardening release)
• Meraki (security hardening release)
• NX-OS Software for MDS 9000, Nexus 3000, 7000, and 9000 Series Switches, Nexus 9000 in ACI mode, and UCS Fabric Interconnects (security hardening release)

To remediate vulnerabilities to be disclosed on October 7, 2026, Cisco strongly recommends that customers upgrade to the fixed software indicated in the advisories.

For more information about changes in Cisco PSIRT vulnerability disclosure, see Strengthening the Foundation: A Predictable, Customer-Focused Response to AI-Accelerated Vulnerability Discovery.

<br/>Security Impact Rating: Informational

A vulnerability in the API session-based authentication management of Cisco Catalyst SD-WAN Manager could allow an unauthenticated, remote attacker to access an affected system with privileges of the admin user.

This vulnerability is due to improper handling of URI encoding in an HTTP request, which allows the request to bypass an authentication rule that is intended to restrict access to a specific API endpoint. An attacker could exploit this vulnerability by sending a crafted HTTP request to the API of the affected system. A successful exploit could allow the attacker to bypass authentication and gain access to the API as the admin user.

Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-webauth-xr8beuuU

<br/>Security Impact Rating: Critical <br/>CVE: CVE-2026-76504

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco IOS XR Software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities.  

These vulnerabilities were found during internal testing and are not known to be actively exploited. To assist customers in patching and streamline the disclosure process, Cisco has grouped these issues by their underlying vulnerability class — Common Weakness Enumeration (CWE) — and assigned a single Common Vulnerabilities and Exposures identifier (CVE ID) to each CWE grouping.

Cisco has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities.

This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-iosxr-qg64NcM

<br/>Security Impact Rating: Critical <br/>CVE: CVE-2026-20274,CVE-2026-20275,CVE-2026-20276,CVE-2026-20277,CVE-2026-20278,CVE-2026-20279,CVE-2026-20280

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.

Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftdvirtual-dos-MuenGnYR

This advisory is part of the October 2024 release of the Cisco ASA, FMC, and FTD Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: October 2024 Semiannual Cisco ASA, FMC, and FTD Software Security Advisory Bundled Publication.

<br/>Security Impact Rating: High <br/>CVE: CVE-2024-20260

A vulnerability in the web interface of Cisco Secure Firewall Management Center (FMC) Software could allow an unauthenticated, remote attacker to log in to an affected device using a low-privileged account to access sensitive data within the impacted systems.

This vulnerability is due to the presence of static user credentials for a low-privileged account. An attacker could exploit this vulnerability by using the account to log in to an affected system. A successful exploit could allow the attacker to log in to the affected system and access sensitive data as the low-privileged user. 

Note: If the FMC management interface does not have public internet access, the attack surface that is associated with this vulnerability is reduced.  

Cisco has assigned this security advisory a Security Impact Rating (SIR) of High rather than Medium as the score indicates. The reason is that this vulnerability can be used with other Cisco Secure FMC Software vulnerabilities to elevate privileges.

Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. 

This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc-static-cred-BET3Cjh

This advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of September 16, 2026, Security Advisories. In addition, for further documentation of improvements and fixes in Cisco Secure Firewall products, see Cisco Secure Firewall Adaptive Security Appliance Software, Secure Firewall Threat Defense Software, and Secure Firewall Management Center Software Hardening Release: September 2026.

<br/>Security Impact Rating: High <br/>CVE: CVE-2026-20316

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 unexpectedly, resulting in a denial of service (DoS) condition. 

This vulnerability is due to insufficient error checking when processing HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request to the Remote Access SSL VPN service on an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-vpn-dos-dzv4mQFF

This advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of September 16, 2026, Security Advisories. In addition, for further documentation of improvements and fixes in Cisco Secure Firewall products, see Cisco Secure Firewall Adaptive Security Appliance Software, Secure Firewall Threat Defense Software, and Secure Firewall Management Center Software Hardening Release: September 2026.

<br/>Security Impact Rating: High <br/>CVE: CVE-2026-20349

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 unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.

This vulnerability is due to improper resource management when processing certain DTLS messages. An attacker could exploit this vulnerability by sending a crafted stream of DTLS traffic to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

Cisco has released software updates that address this vulnerability. There are workarounds that address this vulnerability.

This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-dtls-dos-Kp57HkyO

This advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of September 16, 2026, Security Advisories. In addition, for further documentation of improvements and fixes in Cisco Secure Firewall products, see Cisco Secure Firewall Adaptive Security Appliance Software, Secure Firewall Threat Defense Software, and Secure Firewall Management Center Software Hardening Release: September 2026.

<br/>Security Impact Rating: High <br/>CVE: CVE-2026-20250

A vulnerability in the External Database Access feature of Cisco Secure Firewall Management Center (FMC) Software could allow an unauthenticated, remote attacker to execute arbitrary commands as root on an affected device.

This vulnerability is due to insecure deserialization of a user-supplied Java byte stream from a host that is configured in the external database access list. An attacker could exploit this vulnerability by sending a crafted, serialized Java byte stream to a specific TCP port of an affected device. A successful exploit could allow the attacker to execute arbitrary commands on the device and elevate privileges to root.

Notes:

• This vulnerability can be exploited only by an attacker who has control of a host in the external database access list.
• If the FMC management interface does not have public internet access, the attack surface that is associated with this vulnerability is reduced.

Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. 

This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc-javarce-y2NypXwk

This advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of September 16, 2026, Security Advisories. In addition, for further documentation of improvements and fixes in Cisco Secure Firewall products, see Cisco Secure Firewall Adaptive Security Appliance Software, Secure Firewall Threat Defense Software, and Secure Firewall Management Center Software Hardening Release: September 2026.

<br/>Security Impact Rating: Critical <br/>CVE: CVE-2026-20242

Multiple vulnerabilities in Cisco Identity Services Engine (ISE) could allow an authenticated, remote attacker to execute arbitrary commands on the underlying operating system of an affected device. To exploit these vulnerabilities, the attacker must have valid administrative credentials.

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 link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-rce-se7bYU57

This advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of September 16, 2026, Security Advisories. In addition, for further documentation of improvements and fixes in Cisco Identity Services Engine, see Cisco Identity Services Engine Security Hardening Release: September 2026.

<br/>Security Impact Rating: Critical <br/>CVE: CVE-2026-20176,CVE-2026-20211,CVE-2026-20307

Multiple vulnerabilities in Cisco Identity Services Engine (ISE) could allow an authenticated, remote attacker to conduct SQL injections, modify data, or execute arbitrary commands on the underlying operating system on an affected device.

For more information about these vulnerabilities, see the Details section of this advisory.

Note: For CVE-2026-20282 and CVE-2026-20283, Cisco has assigned a Security Impact Rating (SIR) of High rather than Medium as the scores indicate. The reason is that it is easy to get to root from the achieved privilege level.

Cisco has released software updates that address these vulnerabilities. There are workarounds that address one of these vulnerabilities.

This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-mult-vul-ymSsTLCc

This advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of September 16, 2026, Security Advisories. In addition, for further documentation of improvements and fixes in Cisco Identity Services Engine, see Cisco Identity Services Engine Security Hardening Release: September 2026.

<br/>Security Impact Rating: Critical <br/>CVE: CVE-2026-20282,CVE-2026-20283,CVE-2026-20284

Multiple vulnerabilities in Cisco Identity Services Engine (ISE) and Cisco ISE Passive Identity Connector (ISE-PIC) could allow a remote attacker to bypass authentication to the REST API, achieve remote code execution, perform SQL injection, and conduct XML External Entity injection attacks on an affected device.

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 link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-multi-hrP9jQSQ

This advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of September 16, 2026, Security Advisories. In addition, for further documentation of improvements and fixes in Cisco Identity Services Engine, see Cisco Identity Services Engine Security Hardening Release: September 2026.

<br/>Security Impact Rating: Critical <br/>CVE: CVE-2026-76423,CVE-2026-76424,CVE-2026-76425,CVE-2026-76426,CVE-2026-76427,CVE-2026-76428

A vulnerability in the RADIUS feature of Cisco Identity Services Engine (ISE) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.

This vulnerability is due to improper handling of certain RADIUS requests. An attacker could exploit this vulnerability by sending a crafted RADIUS request directly to an affected device. A successful exploit could allow the attacker to cause the ISE node to become unavailable. For single node deployments in that condition, endpoints that have not already authenticated would be unable to access the network until the node comes back up on its own.

Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-RADIUS-dos-wR3hYPMw

This advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of September 16, 2026, Security Advisories. In addition, for further documentation of improvements and fixes in Cisco Identity Services Engine, see Cisco Identity Services Engine Security Hardening Release: September 2026.

<br/>Security Impact Rating: High <br/>CVE: CVE-2026-20352

Multiple vulnerabilities in Cisco Secure Firewall Management Center (FMC) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated attacker to perform an sftunnel authentication bypass or sftunnel denial of service (DoS) attack.

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 link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmcftd-sftun-multivulns-WGVHOrN3

This advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of September 16, 2026, Security Advisories. In addition, for further documentation of improvements and fixes in Cisco Secure Firewall products, see Cisco Secure Firewall Adaptive Security Appliance Software, Secure Firewall Threat Defense Software, and Secure Firewall Management Center Software Hardening Release: September 2026.

<br/>Security Impact Rating: High <br/>CVE: CVE-2026-20295,CVE-2026-20323

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.

Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls1.3-dos-dLxwFWgF

This advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of September 16, 2026, Security Advisories. In addition, for further documentation of improvements and fixes in Cisco Secure Firewall products, see Cisco Secure Firewall Adaptive Security Appliance Software, Secure Firewall Threat Defense Software, and Secure Firewall Management Center Software Hardening Release: September 2026.

<br/>Security Impact Rating: High <br/>CVE: CVE-2026-20135

Multiple vulnerabilities in Cisco Identity Services Engine (ISE) could allow an unauthenticated, local attacker to either conduct an authentication bypass or disclose sensitive information.

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 link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-multi-vuln-kWLeNnRD

This advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of September 16, 2026, Security Advisories. In addition, for further documentation of improvements and fixes in Cisco Identity Services Engine, see Cisco Identity Services Engine Security Hardening Release: September 2026.

<br/>Security Impact Rating: Medium <br/>CVE: CVE-2026-20071,CVE-2026-20072

Multiple vulnerabilities in Cisco Secure Firewall Management Center (FMC) Software could allow a remote attacker to gain root access, download sensitive files, perform a SQL injection attack, or cause a denial of service (DoS) condition.

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 link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc-mulivulns-4PsnFwvx

This advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of September 16, 2026, Security Advisories. In addition, for further documentation of improvements and fixes in Cisco Secure Firewall products, see Cisco Secure Firewall Adaptive Security Appliance Software, Secure Firewall Threat Defense Software, and Secure Firewall Management Center Software Hardening Release: September 2026.

<br/>Security Impact Rating: Critical <br/>CVE: CVE-2026-20340,CVE-2026-20341,CVE-2026-20342,CVE-2026-20343,CVE-2026-20344

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Secure Firewall Adaptive Security Appliance (ASA) Software, Cisco Secure Firewall Threat Defense (FTD) Software and Cisco Secure Firewall Management Center (FMC) Software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities.  

These vulnerabilities were found during internal testing. Two of them are known to be actively exploited. For more information, see the following advisories: Cisco Secure Firewall Management Center Software Static Credential Vulnerability and Cisco Secure Firewall Management Center Software Authentication Bypass Vulnerability. To assist customers in patching and to streamline the disclosure process, Cisco has grouped these issues by their underlying vulnerability class — Common Weakness Enumeration (CWE) — and assigned a single Common Vulnerabilities and Exposures Identifier (CVE ID) to each CWE grouping.

Cisco has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities.

This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-asaftdfmc-uvpPROhN

This advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of September 16, 2026, Security Advisories. 

<br/>Security Impact Rating: Critical <br/>CVE: CVE-2026-20329,CVE-2026-20330,CVE-2026-20331,CVE-2026-20332,CVE-2026-20333,CVE-2026-20334,CVE-2026-20335,CVE-2026-20336

A vulnerability in the DNS over TCP implementation 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 TCP DNS response handler to unexpectedly restart, causing the device to reload.

This vulnerability is due to a logic error when parsing a DNS query and tracking the size of the incoming buffers. An attacker could exploit this vulnerability by formatting a crafted reply to a DNS query sent from the targeted device. A successful exploit could allow the attacker to cause the device to reload, causing a denial of service (DoS) condition.

Note: The attacker must be able to respond to DNS queries from the device, either by controlling the DNS service or through a machine-in-the-middle attack.

Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-tcpdns-dos-p6dUnjr5

This advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of September 16, 2026, Security Advisories. In addition, for further documentation of improvements and fixes in Cisco Secure Firewall products, see Cisco Secure Firewall Adaptive Security Appliance Software, Secure Firewall Threat Defense Software, and Secure Firewall Management Center Software Hardening Release: September 2026.

<br/>Security Impact Rating: Medium <br/>CVE: CVE-2026-20248

A vulnerability in the web-based management interface of Cisco ThousandEyes Virtual Appliance could allow an authenticated, remote attacker to inject arbitrary operating system commands.

This vulnerability is due to improper validation of user-supplied input to the web-based management interface. An attacker could exploit this vulnerability by saving configuration details that contain malicious values. A successful exploit could allow the attacker to execute arbitrary operating system commands with root privileges. To exploit this vulnerability, the attacker must have valid administrative credentials.

Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-teva-os-command-W4GAO6jp

<br/>Security Impact Rating: Medium <br/>CVE: CVE-2026-20350