CRITICAL 9.3 NVD
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 unauthenticat
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.
References
- https://forum.proxmox.com/threads/proxmox-virtual-environment-security-advisories.149331/p
- https://git.proxmox.com/?p=pve-access-control.git;a=commit;h=032e7d6d441f89a48cadfd7f47e95
- https://git.proxmox.com/?p=pve-access-control.git;a=commit;h=032e7d6d441f89a48cadfd7f47e95
- https://www.vulncheck.com/advisories/proxmox-ve-authentication-bypass-via-tfa-challenge-pa
This critical severity vulnerability with a CVSS score of 9.3 was published on 2026-09-01 via NVD.
Risk Timeline
CVE Disclosed2026-09-01 · -1 days ago
Remediation Resources
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