CVE-2023-54391

CVE Enrichment

CVSS: 9.3 CRITICAL
EPSS: 3.25%
EPSS Percentile: 88.02%
CISA KEV: Not listed

Description

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.

Technical Details

CVSS Version: 4.0
CNA / NVD Source: disclosure@vulncheck.com
Published: 02-Sep-2026 05:17
Last Modified: 09-Sep-2026 03:18
EPSS Date: 2026-10-13
CWE: CWE-304

CVSS Vector


            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

References

Last enrichment sync: 14-Oct-2026 07:57
Sources: NVD · FIRST EPSS · CISA KEV
Latest successful provider update; providers refresh independently.

Reported Context (1)

CVE-2023-54391 Recorded Future Reports 94 High-Impact Vulnerabilities in September 2026, Including 80 Actively Exploited

CVE (76)

Malware (6)

Threat Actors (8)

Vendors (10)

Products (67)

Tools (7)

Industries (1)

Countries (2)

Note: Related entities, including threat actors, malware, CVEs, MITRE ATT&CK techniques, vendors, products, tools, countries, and industries, are shown when they appear in the same reporting. Their presence does not necessarily mean they were targeted, compromised, vulnerable, responsible for the activity, or directly involved in the incident.