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CVE coverage

CVE-2026-20127

CVSS 10.0 Actively exploited (KEV) 6 detections found
View on NVD →
A vulnerability in the peering authentication in Cisco Catalyst SD-WAN Controller, formerly SD-WAN vSmart, Cisco Catalyst SD-WAN Manager, formerly SD-WAN vManage, and Cisco Catalyst SD-WAN Validator, formerly SD-WAN vBond, could allow an unauthenticated, remote attacker to bypass authentication and obtain administrative privileges on an affected system. This vulnerability exists because the peering authentication mechanism in an affected system is not working properly. An attacker could exploit this vulnerability by sending crafted requests to an affected system. A successful exploit could allow the attacker to log in to an affected Cisco Catalyst SD-WAN Controller as an internal, high-privileged, non-root user account. Using this account, the attacker could access NETCONF, which would then allow the attacker to manipulate network configuration for the SD-WAN fabric. 

Detection rules

Source Rule Status Updated
splunk Cisco SD-WAN Multiple Source IP vManage Admin SSH Authentication production 2026-06-09
splunk Cisco SD-WAN Multiple SSH key Authentication from Same Source production 2026-06-09
splunk Cisco SD-WAN - Arbitrary File Overwrite Exploitation Activity production 2026-05-13
splunk Cisco SD-WAN - Low Frequency Rogue Peer production 2026-05-13
splunk Cisco SD-WAN - Peering Activity production 2026-05-13
splunk Cisco SD-WAN - Uncommon User-Agent Multi-URI Activity production 2026-05-13