Critical Analysis: CVE-2026-76504 - Cisco Catalyst SD-WAN Manager Hex Encoding Vulnerability... — October 3, 2026

Published 03 Oct 2026 · vulnerability management, CVE analysis, threat intelligence, security operations, cybersecurity news

As senior cybersecurity analysts at AGMP Partners, we constantly track and dissect critical vulnerabilities that impact our clients and the broader digital landscape. Today, I want to dive deep into a recently disclosed critical vulnerability: CVE-2026-76504, a Hex Encoding Vulnerability in Cisco Catalyst SD-WAN Manager. Published on October 3, 2026, this flaw represents a significant attack surface exposure, particularly given the pervasive adoption of SD-WAN technologies. Initial Discovery and Context This vulnerability, designated CVE-2026-76504, was brought to light by an independent security researcher during a focused red team engagement targeting large enterprise infrastructure, subsequently validated and disclosed by Cisco's Product Security Incident Response Team (PSIRT). The affected component is the Cisco Catalyst SD-WAN Manager (formerly vManage), specifically in its handling