CVE-2023-54391 — Proxmox VE 7.0-8.0 Authentication Bypass via tfa-challenge Parameter
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 a…
Published: 2026-09-01 · CVSS: 9.3 · CVSS 4.0
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7