UAT-8616 exploits Cisco Catalyst SD-WAN CVE-2026-20182; 10+ clusters exploit companion February 2026 CVEs; CISA Emergency Directive ED-26-03 issued

Cisco Talos published an updated exploitation bulletin on 2026-05-14 documenting active, in-the-wild exploitation of CVE-2026-20182 — a complete pre-authentication bypass in the Cisco Catalyst SD-WAN Controller — by UAT-8616, a highly sophisticated actor assessed to have operated against Cisco SD-WAN infrastructure since at least 2023 with ORB-network-hosted tooling (Cisco Talos, 2026-05-14). Separately, at least 10 additional less-sophisticated threat clusters (Cluster #1 through #10 in Talos's taxonomy) have been exploiting the companion February 2026 CVEs (CVE-2026-20133, CVE-2026-20128, CVE-2026-20122) since March 2026 (Rapid7, 2026-05-14). Post-exploitation activity includes deployment of Godzilla, Behinder, and XenShell webshells; AdaptixC2, Sliver, and Nimplant C2 frameworks; XMRig cryptomining; and log-wiping to remove syslog, wtmp, and lastlog artefacts. UAT-8616 additionally performs a targeted version-downgrade to re-expose CVE-2022-20775 (local privilege escalation to root), then restores the original version to erase the downgrade trace. CISA issued Emergency Directive ED-26-03 on 2026-05-14 designating this the sixth Cisco SD-WAN CVE exploited in 2026; companion CVEs CVE-2026-20133, CVE-2026-20128, and CVE-2026-20122 were being exploited by multiple clusters since March 2026. Snort detection signatures: 66482–66483 (CVE-2026-20182), 66468–66469 (CVE-2026-20133), 66461–66462 (CVE-2026-20122). Hunt: look for unexpected NETCONF sessions on TCP/830 from Controller processes; additions to /home/vmanage-admin/.ssh/authorized_keys; out-of-sequence software downgrade/upgrade log events in vManage; and peer registrations from unknown ASNs in show sdwan control connections.