Vulnerability-Lookup

GHSA-M457-GRCF-698X

Vulnerability from github – Published: 2026-09-02 00:31 – Updated: 2026-09-02 00:31

Details

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.

Severity

9.8 (Critical)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

9.3 (Critical)


                  
                    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

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2023-54391"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-304"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-01T22:17:10Z",
    "severity": "CRITICAL"
  },
  "details": "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.",
  "id": "GHSA-m457-grcf-698x",
  "modified": "2026-09-02T00:31:29Z",
  "published": "2026-09-02T00:31:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-54391"
    },
    {
      "type": "WEB",
      "url": "https://forum.proxmox.com/threads/proxmox-virtual-environment-security-advisories.149331/page-4#post-867929"
    },
    {
      "type": "WEB",
      "url": "https://git.proxmox.com/?p=pve-access-control.git;a=commit;h=032e7d6d441f89a48cadfd7f47e957c8a561c022"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/proxmox-ve-authentication-bypass-via-tfa-challenge-parameter"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "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/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",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2023-54391 (GCVE-0-2023-54391)

Vulnerability from cvelistv5 – Published: 2026-09-01 21:59 – Updated: 2026-09-02 11:59 Unsupported When Assigned X_Known Exploited Vulnerability

Title

Proxmox VE 7.0-8.0 Authentication Bypass via tfa-challenge Parameter

Summary

Severity

9.3 (Critical)


                        
                          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

9.8 (Critical)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: yes Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-02 11:55 UTC

CWE

CWE-304 - Missing Critical Step in Authentication

Assigner

VulnCheck mitre root

References

3 references

URL	Tags
https://forum.proxmox.com/threads/proxmox-virtual…	vendor-advisory
https://git.proxmox.com/?p=pve-access-control.git…	patch
https://www.vulncheck.com/advisories/proxmox-ve-a…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
Proxmox Server Solutions GmbH	Proxmox Virtual Environment (VE)	Affected: 7.0 , ≤ 7.4 (custom) Affected: 8.0 (custom)

Date Public

2023-07-14 00:00

Credits

Kamil Rakowski Nathan Xavier Golez Sagnik Sasmal

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2023-54391",
                "options": [
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                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-02T11:55:35.310993Z",
                "version": "2.0.3"
              },
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          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
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          "defaultStatus": "unaffected",
          "product": "Proxmox Virtual Environment (VE)",
          "vendor": "Proxmox Server Solutions GmbH",
          "versions": [
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              "lessThanOrEqual": "7.4",
              "status": "affected",
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              "versionType": "custom"
            },
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              "status": "affected",
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            }
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          "type": "finder",
          "value": "Kamil Rakowski"
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          "type": "finder",
          "value": "Nathan Xavier Golez"
        },
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          "lang": "en",
          "type": "finder",
          "value": "Sagnik Sasmal"
        }
      ],
      "datePublic": "2023-07-14T00:00:00.000Z",
      "descriptions": [
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          "lang": "en",
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      ],
      "metrics": [
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            "Recovery": "NOT_DEFINED",
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            "baseScore": 9.3,
            "baseSeverity": "CRITICAL",
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            "valueDensity": "NOT_DEFINED",
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            "vulnIntegrityImpact": "HIGH",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
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        },
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    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2023-54391",
    "datePublished": "2026-09-01T21:59:12.692Z",
    "dateReserved": "2026-09-01T21:23:55.860Z",
    "dateUpdated": "2026-09-02T11:59:20.773Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

GHSA-M457-GRCF-698X

CVE-2023-54391 (GCVE-0-2023-54391)

Tags

Sightings

Nomenclature