Advanced Malware Protection

Critical Vulnerability CVE-2026-76519 in Cisco Secure Email Gateway Allows Arbitrary File Writes Without Authentication

Cisco Systems has disclosed a critical vulnerability in its Cisco Secure Email Gateway product that affects the Advanced Malware Protection feature responsible for processing email attachments. The flaw, tracked as CVE-2026-76519, permits unauthenticated attackers to write arbitrary files to the underlying operating system by sending a specially crafted email attachment. Successful exploitation can lead to remote command execution with root privileges. The vulnerability received a CVSS v3.1 base score of 9.8 and is rated Critical. Cisco confirmed active exploitation of the issue in October 2026, shortly after publishing the security advisory on October 14, 2026. This marks the second publicly disclosed exploited vulnerability in the product within a short period, though the flaws are unrelated.