{
    "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": "2026-09-01T21:59:53.698Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
                "shortName": "VulnCheck",
                "dateUpdated": "2026-09-01T21:59:53.698Z"
            },
            "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"
                        }
                    ]
                }
            ],
            "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=032e7d6d441f89a48cadfd7f47e957c8a561c022",
                    "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"
            }
        }
    }
}