As part of Cisco's ongoing commitment to proactive security and product quality, engineering teams 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.

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Secure Email Gateway and Cisco Secure Email and Web Manager 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 Cisco Secure Email Gateway SQL Injection Vulnerability ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esa-inj-2bLVGmhX"] and Cisco Secure Email Gateway Arbitrary File Write Vulnerability ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esa-afw-zqYJkjxp"]. 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.

On October 21, 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: Expressway Series (security hardening release) IOS XR Software for ASR 9000 Series Routers Secure Client Snort (security hardening release) Unified Communications products (security hardening release) To remediate vulnerabilities to be disclosed on October 21, 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 ["https://blogs.cisco.com/security/strengthening-the-foundation-a-predictable-customer-focused-response-to-ai-accelerated-vulnerability-discovery"].

A vulnerability in the Advanced Malware Protection (AMP) feature of Cisco Secure Email Gateway could allow an unauthenticated, remote attacker to write arbitrary files on the underlying operating system. This vulnerability is due to improper handling of email attachments when the file reputation service is enabled. An attacker could exploit this vulnerability by sending an email that contains a crafted attachment through an affected device. A successful exploit could allow the attacker to write arbitrary files and execute commands with root privileges on the underlying operating system. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. For further documentation of improvements and fixes in Cisco Secure Email Gateway, see Cisco Secure Email Gateway and Secure Email and Web Manager Security Hardening Release: September 2026 ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-esa-dfCrfXkm"].

A vulnerability in the Unified Extensible Firmware Interface (UEFI) Shell implementation of Cisco UCS Servers and UCS-based appliances could allow an authenticated attacker with valid credentials for a user account with the role of user or admin or an unauthenticated attacker with physical access to an affected device to bypass UEFI Secure Boot validation checks and execute unauthorized software. This vulnerability is due to the availability of memory write commands in the UEFI Shell while UEFI Secure Boot is enabled on a device. An attacker could exploit this vulnerability by selecting the UEFI Shell boot option at boot time and using available shell commands to modify UEFI memory variables. A successful exploit could allow the attacker to manipulate the preboot environment, overwrite UEFI Secure Boot-related memory values, and execute unauthorized software on the affected device. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

A vulnerability in the NX-API feature of Cisco NX-OS Software could allow an unauthenticated, remote attacker to execute arbitrary code with root privileges or cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient input validation of data that is sent to the NX-API. An attacker could exploit this vulnerability by sending a crafted HTTP request to the NX-API of an affected device. A successful exploit could allow the attacker to execute arbitrary code with root privileges and could cause process crashes, which could result in a reload of the device and a DoS condition. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. 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 October 7, 2026, Security Advisories ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-notice-fBn58ELx"]. For further documentation of improvements and fixes in Cisco NX-OS Software, see Cisco NX-OS Software Security Hardening Release: October 2026 ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-nxosw1-cWzSbtR"].

On October 7, 2026, the Cisco Product Security Incident Response Team (PSIRT) published the advisories that are listed in the following tables. To remediate the vulnerabilities that were disclosed on October 7, 2026, Cisco strongly recommends that customers upgrade to the fixed software that is 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 ["https://blogs.cisco.com/security/strengthening-the-foundation-a-predictable-customer-focused-response-to-ai-accelerated-vulnerability-discovery"]. Cisco NX-OS Software Cisco Security Advisory CVE ID Security Impact Rating CVSS Base Score Cisco NX-OS Software Security Hardening Release: October 2026 ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-nxosw1-cWzSbtR"] CVE-2026-76455 CVE-2026-76456 CVE-2026-76457 CVE-2026-76459 CVE-2026-76458 CVE-2026-76453 Critical 9.8 Cisco Nexus 3000 and 9000 Series Switches MPLS OAM Remote Code Execution Vulnerability ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-moam-rce-uBTzYV7"] CVE-2026-76465 Critical 9.8 Cisco Nexus 3000 and 9000 Series Switches NGOAM Remote Code Execution Vulnerabilities ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ngoam-rce-LWK…

Multiple vulnerabilities in the web-based management interface and API endpoints of Cisco License On-Prem, formerly Cisco Smart Software Manager On-Prem (SSM On-Prem), could allow a remote attacker to gain unauthorized access, access sensitive information, cause a denial of service (DoS) condition, or elevate privileges. For more information about these vulnerabilities, see the Details ["#details"] section of this advisory. Cisco has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities. For further documentation of improvements and fixes in Cisco License On-Prem, see Cisco License (Smart Software Manager) On-Prem Security Hardening Release ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-ssm-Ph77wdhf"].

A vulnerability in Cisco NX-OS Software could allow an unauthenticated, remote attacker to exhaust system resources, causing a denial of service (DoS) condition. This vulnerability exists because rate limiting was improperly applied to some protocols. An attacker could exploit this vulnerability by sending a high rate of UDP or TCP connections to a data plane interface on an affected device. A successful exploit could allow the attacker to cause instability to various routing and control plane protocols through some packet loss and temporary disruptions, causing a DoS condition. This DoS condition will clear without manual intervention soon after the high rate of traffic is stopped. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. 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 October 7, 2026, Security Advisories ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-notice-fBn58ELx"]. For further documentation of improvements and fixes in Cisco NX-OS Software, see Cisco NX-OS Software Security Hardening Release: October 2026 ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-nxosw1-cWzSbtR"].

A vulnerability in the Python interpreter of Cisco NX-OS Software could allow an authenticated, local attacker with low privileges to escape the Python sandbox and gain unauthorized access to the underlying operating system of an affected device. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by manipulating specific functions within the Python interpreter. A successful exploit could allow an attacker to escape the Python sandbox and execute arbitrary commands on the underlying operating system with the privileges of the authenticated user. Note: An attacker must be authenticated with Python execution privileges to exploit this vulnerability. For more information regarding Python execution privileges, see product-specific documentation, such as the Cisco NX-OS Security with Python ["https://www.cisco.com/c/en/us/td/docs/dcn/nx-os/nexus9000/106x/programmability/cisco-nexus-9000-series-nx-os-programmability-guide-106x/m-n9k-python-api-101x.html?bookSearch=true#concept_A2CFF094ADCB414C983EA06AD8E9A410"] section of the Cisco Nexus 9000 Series NX-OS Programmability Guide. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. 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 October 7, 2026, Security Advisories ["htt…