AsyncOS

Cisco Confirms Active Exploitation of Critical Secure Email Gateway Flaw Allowing Root Command Execution

Cisco has confirmed active exploitation of a critical vulnerability in its Secure Email Gateway product that allows attackers to execute arbitrary commands with root privileges. The flaw, tracked as CVE-2026-76461 with a CVSS score of 9.8, stems from insufficient input validation in the message analysis logic of AsyncOS. Attackers can trigger the issue by sending a specially crafted email containing malicious SQL instructions, which leads to arbitrary SQL command execution and full root access on affected appliances. The vulnerability impacts physical and virtual deployments running AsyncOS versions 15.5 and earlier, 16.0, and 16.5. Patches are available in versions 15.5.5-0141, 16.0.4-302, and 16.5.0-780, while the Secure Email and Web Manager and Secure Web Appliance remain unaffected. CISA added the CVE to its Known Exploited Vulnerabilities catalog on September 14 and set a September 17 remediation deadline for federal agencies.

Cisco Secure Email Gateway CVE-2026-76461 Critical SQL Injection Flaw Exploited in the Wild for Root Access

Cisco has confirmed active exploitation of CVE-2026-76461, a CVSS 9.8 critical SQL injection vulnerability in Secure Email Gateway. The flaw resides in AsyncOS mail parsing logic and allows unauthenticated attackers to execute arbitrary commands as root simply by sending a specially crafted email. No user interaction, authentication, or workarounds exist, leaving immediate patching as the only mitigation. Affected versions include all releases up to 15.5, 16.0, and 16.5; fixed builds are 15.5.5-014, 16.0.4-302, and 16.5.0-780. Because the gateway sits at the network perimeter with high privileges, successful compromise enables long-term email interception, lateral movement, and internal phishing campaigns. Organizations should examine mail_logs for patterns such as COPY.*TO PROGRAM and cross-check network telemetry for anomalous outbound connections.