CVE-2023-54391: critical vulnerability in Proxmox Virtual Environment (VE)
Proxmox VE 7.0-8.0 Authentication Bypass via tfa-challenge Parameter
Published · Updated
85Vexday Risk Score
Patch now. It exploitation observed by VulnCheck and has a working public exploit.
ssvc Actcvss 9.3epss 3.1%
from disclosure to weapon2 days
Published on NVDSep 1
1st PoC+2d
VulnCheckSep 1
exploitation probability
3.1%top 13% of all CVEs
observed exploitation
yesVulnCheck
4 public exploit(s)
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:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Affected products
Proxmox Server Solutions GmbH · Proxmox Virtual Environment (VE)public PoCs found — 4
githubgithub.com/alexand0www/CVE-2023-54391-RCE★ 2githubgithub.com/alexandrov666/CVE-2023-54391-RCE★ 0githubgithub.com/disqualifier/psa-2026-00043-recovery★ 0vulncheckvulncheck.com/xdb/00c50ea74c4aunverified⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
References
https://forum.proxmox.com/threads/proxmox-virtual-environment-security-advisories.149331/page-4#post-867929https://git.proxmox.com/?p=pve-access-control.git;a=commit;h=032e7d6d441f89a48cadfd7f47e957c8a561c022https://git.proxmox.com/?p=pve-access-control.git;a=commit;h=0f3d14d6be4d9f23e511701696a529ef3b7ffd61https://www.vulncheck.com/advisories/proxmox-ve-authentication-bypass-via-tfa-challenge-parameter