CVE-2022-35507

Name: CVE-2022-35507
Creator: NVD / NIST
Published: 2022-12-04T19:15:09.85+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.1/10EPSS 1.38%

Last modified Jun 17, 2026

CVE-2022-35507 is a high-severity vulnerability rated 7.1/10 on the CVSS scale. 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. EPSS estimates a 1.38% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

7.1/10

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

EPSS Probability

1.38%

68.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Proxmox	Proxmox Mail Gateway	All versions
Proxmox	Pve Http Server	< 4.1-3
Proxmox	Virtual Environment	All versions

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/Exploit, Patch, Technical Description, Third Party Advisory
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/Exploit, Patch, Technical Description, Third Party Advisory

Timeline

Published: Dec 4, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2022-35507?

How severe is CVE-2022-35507?

CVE-2022-35507 has a CVSS score of 7.1/10 (HIGH severity). The EPSS model estimates a 1.38% probability of exploitation in the next 30 days.

How do I fix CVE-2022-35507?

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-2022-35507?

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

Scan your code now

Source: NVD / NIST