CVE-2026-20122 Elastic Security · Elastic

Detect Cisco Catalyst SD-WAN Manager Privileged API Abuse (CVE-2026-20122) in Elastic Security

Detects exploitation of CVE-2026-20122, a critical vulnerability in Cisco Catalyst SD-WAN Manager involving incorrect use of privileged APIs (CWE-648). This KEV-listed flaw allows attackers to invoke privileged API endpoints without proper authorization, potentially enabling unauthorized configuration changes, credential harvesting, or full SD-WAN infrastructure takeover. Active exploitation has been observed in the wild per CISA Emergency Directive ED-26-03.

MITRE ATT&CK

Tactic
Initial Access Privilege Escalation Defense Evasion Lateral Movement

Elastic Detection Query

Elastic Security (Elastic)
eql 
sequence by source.ip with maxspan=5m
  [network where
    destination.port in (443, 8443, 8080) and
    url.path : ("/dataservice/admin*", "/dataservice/system*", "/dataservice/device/action*", "/dataservice/template*", "/dataservice/settings/configuration*", "/dataservice/certificate*", "/dataservice/aaa*") and
    http.request.method in ("POST", "PUT", "DELETE", "PATCH") and
    http.response.status_code in (200, 201, 204)
  ] with runs=3
critical severity medium confidence

EQL sequence rule detecting three or more successful privileged API mutations from the same source IP within 5 minutes, targeting known Cisco SD-WAN Manager administrative API namespaces consistent with CVE-2026-20122 abuse.

Data Sources

Elastic Network LogsPacketbeatWeb Application Firewall logs

Required Tables

logs-network*logs-apm*packetbeat-*

False Positives & Tuning

  • Bulk API-driven provisioning workflows executed by authorized network automation accounts
  • SD-WAN health monitoring agents that authenticate and query multiple admin endpoints in rapid succession
  • Load balancer health checks misconfigured to probe privileged API paths

Other platforms for CVE-2026-20122

Microsoft Sentinel (KQL) Splunk (SPL) IBM QRadar (QRadar) Sumo Logic CSE (Sumo) Google Chronicle (YARA-L) CrowdStrike LogScale (LogScale) All platforms (combined) →

Testing Methodology

Validate this detection against 4 adversary techniques from Atomic Red Team. Each test below lists the behaviour to exercise and the telemetry you should expect to see. Executable commands and cleanup steps are available with Pro.

  1. Test 1Unauthenticated SD-WAN Manager Privileged API Probe

    Expected signal: HTTP GET requests to /dataservice/admin/user, /dataservice/system/information, /dataservice/aaa/usergroup, /dataservice/certificate/list from the test host to port 8443, logged in vManage access logs and network flow.

  2. Test 2Privileged API Admin Account Creation Simulation

    Expected signal: POST to /dataservice/aaa/user with a new username payload logged in vManage audit log, network capture showing the request body containing userName and group fields.

  3. Test 3SD-WAN Manager Template Enumeration and Exfiltration Simulation

    Expected signal: Sequential GET requests to /dataservice/template/device, /dataservice/template/feature, /dataservice/device, and /dataservice/device/action/list within a short timeframe from a single source IP.

  4. Test 4Rapid Privileged API Burst from Single Source

    Expected signal: 21+ HTTP requests across 7 distinct privileged API paths within seconds, all from the same source IP, logged in vManage access logs and network telemetry.

Last updated: 2026-06-19 Research depth: standard
References (4)

Unlock Pro Content

Get the full detection package for CVE-2026-20122 including response playbook, investigation guide, and atomic red team tests.

Response PlaybookInvestigation GuideHunting QueriesAtomic Red Team TestsTuning Guidance
Sign Up for Pro View Pricing

Related Detections

Tactic Hubs

TA0001Initial AccessTA0004Privilege EscalationTA0005Defense EvasionTA0008Lateral Movement

Related Techniques

T1190Exploit Public-Facing ApplicationT1078Valid AccountsT1098Account ManipulationT1021Remote Services

Same Tactic: Initial Access

Popular Detections