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CVE coverage

CVE-2026-76504

CVSS 9.8 Actively exploited (KEV) no coverage
View on NVD →
A vulnerability in the API session-based authentication management of Cisco Catalyst SD-WAN Manager could allow an unauthenticated, remote attacker to access an affected system with privileges of the admin user. This vulnerability is due to improper handling of URI encoding in an HTTP request, which allows the request to bypass an authentication rule that is intended to restrict access to a specific API endpoint. An attacker could exploit this vulnerability by sending a crafted HTTP request to the API of the affected system. A successful exploit could allow the attacker to bypass authentication and gain access to the API as the admin user.

Detection rules

No detection found — yet
None of Sigma, Elastic, Splunk ESCU, YARA, Microsoft Sentinel, Snort, or Suricata currently has a rule referencing CVE-2026-76504.

This CVE is on CISA's Known Exploited Vulnerabilities list. It is being exploited in the wild with no public detection rule — worth writing one.