What’s Vulnerable › Vulnerabilities

CVE-2022-35507

• Severity: high (CVSS 7.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.5% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2022-12-04 · updated 2026-06-17
• Weakness: CWE-74

Description

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.

Affected products

• Proxmox Mail Gateway: all versions
• Proxmox Pve Http Server: before 4.1-3 — fixed in 4.1-3
• Proxmox Virtual Environment: all versions

How to fix

Upgrade to a fixed version: Proxmox Pve Http Server 4.1-3. Check the vendor advisory for mitigations.

References

• https://git.proxmox.com/?p=pve-http-server.git%3Ba=commitdiff%3Bh=936007ae0241811093155000486da171379c23c2
• https://starlabs.sg/blog/2022/12-multiple-vulnerabilites-in-proxmox-ve--proxmox-mail-gateway/
• https://git.proxmox.com/?p=pve-http-server.git%3Ba=commitdiff%3Bh=936007ae0241811093155000486da171379c23c2
• https://starlabs.sg/blog/2022/12-multiple-vulnerabilites-in-proxmox-ve--proxmox-mail-gateway/

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