CVE-2023-43320

Name: CVE-2023-43320
Creator: NVD / NIST
Published: 2023-09-27T23:15:12.113+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 0.99%

Last modified Jun 17, 2026

CVE-2023-43320 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. An issue in Proxmox Server Solutions GmbH Proxmox VE v.5.4 thru v.8.0, Proxmox Backup Server v.1.1 thru v.3.0, and Proxmox Mail Gateway v.7.1 thru v.8.0 allows a remote authenticated attacker to escalate privileges via bypassing the two-factor authentication component.. EPSS estimates a 0.99% chance of exploitation in the next 30 days.

Description

An issue in Proxmox Server Solutions GmbH Proxmox VE v.5.4 thru v.8.0, Proxmox Backup Server v.1.1 thru v.3.0, and Proxmox Mail Gateway v.7.1 thru v.8.0 allows a remote authenticated attacker to escalate privileges via bypassing the two-factor authentication component.

Metrics

CVSS 3.1

8.8/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

0.99%

58.1th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions
Proxmox	Backup Server	>= 1.1, <= 3.0
Proxmox	Proxmox Mail Gateway	>= 7.1, <= 8.0
Proxmox	Virtual Environment	>= 5.4, <= 8.0

References

http://packetstormsecurity.com/files/176967/Proxmox-VE-7.4-1-TOTP-Brute-Force.html
https://bugzilla.proxmox.com/show_bug.cgi?id=4579Issue Tracking, Vendor Advisory
https://bugzilla.proxmox.com/show_bug.cgi?id=4584Issue Tracking, Vendor Advisory
https://github.com/proxmox/proxmox-rs/commit/50b793db8d3421bbfe2bce060a486263f18a90cbPatch
http://packetstormsecurity.com/files/176967/Proxmox-VE-7.4-1-TOTP-Brute-Force.html
https://bugzilla.proxmox.com/show_bug.cgi?id=4579Issue Tracking, Vendor Advisory
https://bugzilla.proxmox.com/show_bug.cgi?id=4584Issue Tracking, Vendor Advisory
https://github.com/proxmox/proxmox-rs/commit/50b793db8d3421bbfe2bce060a486263f18a90cbPatch

Timeline

Published: Sep 27, 2023
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2023-43320?

How severe is CVE-2023-43320?

CVE-2023-43320 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 0.99% probability of exploitation in the next 30 days.

How do I fix CVE-2023-43320?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2023-43320?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST