Vulnerability in Proxmox Server Solutions Gmbh Virtual Environment (Ve)

CVE-2023-54391

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.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2023-54391?
CVE-2023-54391 is a critical-severity vulnerability in Proxmox Server Solutions Gmbh Virtual Environment (Ve), classified under Missing Critical Step in Authentication. CVSS score: 9.8/10. Published 2026-09-01.
How severe is CVE-2023-54391?
Critical severity. CVSS v3 base score is 9.8 out of 10.