Proxmox Virtual Environment is an open-source server management platform for enterprise virtualization. Insufficient safeguards against malicious API response values allow authenticated attackers with 'Sys.Audit' or 'VM.Monitor' privileges to download arbitrary host files via the API. When handling the result from a request handler before returning it to the user, the handle_api2_request function will check for the ‘download’ or ‘data’->’download’ objects inside the request handler call response object. If present, handle_api2_request will read a local file defined by this object and return it to the user. Two endpoints were identified which can control the object returned by a request handler sufficiently that the ’download’ object is defined and user controlled. This results in arbitrary file read. The privileges of this file read can result in full compromise of the system by various impacts such as disclosing sensitive files allowing for privileged session forgery.

Proxmox proxmox-widget-toolkit before 4.0.9, as used in multiple Proxmox products, allows XSS via the edit notes feature.

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.

A reflected cross-site scripting (XSS) vulnerability in Proxmox Virtual Environment prior to v7.2-3 allows remote attackers to execute arbitrary web scripts or HTML via non-existent endpoints under path /api2/html/.

Proxmox Virtual Environment (PVE) and Proxmox Mail Gateway (PMG) are vulnerable to SSRF when proxying HTTP requests between pve(pmg)proxy and pve(pmg)daemon. An attacker with an unprivileged account can craft an HTTP request to achieve SSRF and file disclosure of any files on the server. Also, in Proxmox Mail Gateway, privilege escalation to the root@pam account is possible if the backup feature has ever been used, because backup files such as pmg-backup_YYYY_MM_DD_*.tgz have 0644 permissions and contain an authkey value. This is fixed in pve-http-server 4.1-3.

A response-header CRLF injection vulnerability in the Proxmox Virtual Environment (PVE) and Proxmox Mail Gateway (PMG) web interface allows a remote attacker to set cookies for a victim's browser that are longer than the server expects, causing a client-side DoS. This affects Chromium-based browsers because they allow injection of response headers with %0d. This is fixed in pve-http-server 4.1-3.

Proxmox VE prior to 3.2: 'AccessControl.pm' User Enumeration Vulnerability

Open redirect vulnerability in Proxmox Mail Gateway prior to hotfix 4.0-8-097d26a9 allows remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via the destination parameter.

Multiple cross-site scripting (XSS) vulnerabilities in Proxmox Mail Gateway prior to hotfix 4.0-8-097d26a9 allow remote attackers to inject arbitrary web script or HTML via multiple parameters, related to /users/index.htm, /quarantine/spam/manage.htm, /quarantine/spam/whitelist.htm, /queues/mail/index/, /system/ssh.htm, /queues/mail/?domain=, and /quarantine/virus/manage.htm.

Multiple cross-site scripting (XSS) vulnerabilities in Proxmox Mail Gateway before 3.1-5829 allow remote attackers to inject arbitrary web script or HTML via the (1) state parameter to objects/who/index.htm or (2) User email address to quarantine/spam/manage.htm.