{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2023-54391", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "state": "PUBLISHED", "assignerShortName": "VulnCheck", "dateReserved": "2026-09-01T21:23:55.860Z", "datePublished": "2026-09-01T21:59:12.692Z", "dateUpdated": "2026-10-01T15:19:44.628Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-10-01T15:19:44.628Z" }, "title": "Proxmox VE 7.0-8.0 Authentication Bypass via tfa-challenge Parameter", "descriptions": [ { "lang": "en", "value": "Proxmox Virtual Environment (VE) 7.0 through 8.0 contains an authentication bypass vulnerability in libpve-access-control before 8.0.4 that allows unauthenticated attackers to authenticate as any existing enabled user without a configured second factor by supplying an arbitrary tfa-challenge value in the API login endpoint. Attackers can send a POST request to the access ticket API endpoint with any value in the tfa-challenge parameter to completely skip password verification, gaining unauthorized access including to the root@pam account. All affected releases are end of life." } ], "tags": [ "unsupported-when-assigned", "x_known-exploited-vulnerability" ], "datePublic": "2023-07-14T00:00:00.000Z", "problemTypes": [ { "descriptions": [ { "lang": "en", "cweId": "CWE-304", "description": "Missing Critical Step in Authentication", "type": "CWE" } ] } ], "affected": [ { "defaultStatus": "unaffected", "vendor": "Proxmox Server Solutions GmbH", "product": "Proxmox Virtual Environment (VE)", "versions": [ { "status": "affected", "version": "7.0", "versionType": "custom", "lessThanOrEqual": "7.4" }, { "status": "affected", "version": "8.0", "versionType": "custom" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:a:proxmox:virtual_environment:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.0", "versionEndIncluding": "7.4" }, { "vulnerable": true, "criteria": "cpe:2.3:a:proxmox:virtual_environment:8.0:*:*:*:*:*:*:*" } ] } ] } ], "metrics": [ { "format": "CVSS", "scenarios": [ { "lang": "en", "value": "GENERAL" } ], "cvssV4_0": { "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "subConfidentialityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "subIntegrityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "version": "4.0", "baseSeverity": "CRITICAL", "baseScore": 9.3, "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N" } }, { "format": "CVSS", "scenarios": [ { "lang": "en", "value": "GENERAL" } ], "cvssV3_1": { "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH", "version": "3.1", "baseSeverity": "CRITICAL", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H" } } ], "references": [ { "url": "https://forum.proxmox.com/threads/proxmox-virtual-environment-security-advisories.149331/page-4#post-867929", "name": "Vendor Advisory", "tags": [ "vendor-advisory" ] }, { "url": "https://git.proxmox.com/?p=pve-access-control.git;a=commit;h=032e7d6d441f89a48cadfd7f47e957c8a561c022", "name": "Patch Commit", "tags": [ "patch" ] }, { "url": "https://git.proxmox.com/?p=pve-access-control.git;a=commit;h=0f3d14d6be4d9f23e511701696a529ef3b7ffd61", "name": "Introducing Commit" }, { "url": "https://www.vulncheck.com/advisories/proxmox-ve-authentication-bypass-via-tfa-challenge-parameter", "tags": [ "third-party-advisory" ] } ], "credits": [ { "lang": "en", "value": "Kamil Rakowski", "type": "finder" }, { "lang": "en", "value": "Nathan Xavier Golez", "type": "finder" }, { "lang": "en", "value": "Sagnik Sasmal", "type": "finder" } ], "source": { "discovery": "UNKNOWN" }, "x_generator": { "engine": "vulncheck" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "timestamp": "2026-09-02T11:55:35.310993Z", "id": "CVE-2023-54391", "options": [ { "Exploitation": "none" }, { "Automatable": "yes" }, { "Technical Impact": "total" } ], "role": "CISA Coordinator", "version": "2.0.3" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-09-02T11:59:20.773Z" } } ] } }