Cisco Secure Email Gateway and Secure Email and Web Manager Security Hardening Release: September 2026

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. One of them is known to be actively exploited. For more information, see Cisco Secure Email Gateway SQL Injection Vulnerability . 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-esa-dfCrfXkm Security Impact Rating: Critical CVE: CVE-2026-20353,CVE-2026-76440,CVE-2026-76441,CVE-2026-76442,CVE-2026-76443