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.
Scoring
- Severity
- CRITICAL
- CVSS base score
- 9.8
- 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
- EPSS probability
- 1.75%
- CWE
- CWE-304
- Published
- 2026-09-01
- Last modified
- 2026-09-03
Affected products
- Proxmox Server Solutions GmbH Proxmox Virtual Environment (VE)
- Proxmox Server Solutions GmbH Proxmox Virtual Environment (VE)
Weakness type
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