How severe is CVE-2022-35507?

CVE-2022-35507 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability high.

Is CVE-2022-35507 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-35507?

CVE-2022-35507 primarily affects Proxmox Proxmox Mail Gateway. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2022-35507?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2022-35507 published?

CVE-2022-35507 was published on 2022-12-04 and last updated on 2026-06-17.

CVE-2022-35507

CVE-2022-35507 is a high-severity vulnerability in Proxmox Proxmox Mail Gateway with a CVSS 3.x base score of 7.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-74.

Key facts

Severity: High (CVSS 3.x base score 7.1)
EPSS exploit prediction: 1% (69th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-74
Affected product: Proxmox Proxmox Mail Gateway
Published: 2022-12-04
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2022-35507?: 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.
How severe is CVE-2022-35507?: CVE-2022-35507 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability high.
Is CVE-2022-35507 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-35507?: CVE-2022-35507 primarily affects Proxmox Proxmox Mail Gateway. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2022-35507?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2022-35507 published?: CVE-2022-35507 was published on 2022-12-04 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:proxmox:proxmox_mail_gateway:-:*:*:*:*:*:*:*
cpe:2.3:a:proxmox:pve_http_server:*:*:*:*:*:*:*:*
cpe:2.3:a:proxmox:virtual_environment:-:*:*:*:*:*:*:*

More vulnerabilities in Proxmox Proxmox Mail Gateway

CVE-2022-35508 — Critical (CVSS 9.8): Proxmox Virtual Environment (PVE) and Proxmox Mail Gateway (PMG) are vulnerable to SSRF when proxying HTTP requests…
CVE-2023-43320 — High (CVSS 8.8): 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…
CVE-2015-9058 — Medium (CVSS 6.1): Open redirect vulnerability in Proxmox Mail Gateway prior to hotfix 4.0-8-097d26a9 allows remote attackers to redirect…
CVE-2015-9057 — Medium (CVSS 6.1): Multiple cross-site scripting (XSS) vulnerabilities in Proxmox Mail Gateway prior to hotfix 4.0-8-097d26a9 allow remote…

All CVEs affecting Proxmox Proxmox Mail Gateway →

Other CWE-74 (Improper Neutralization of Special Elements (Injection)) vulnerabilities

CVE-2026-25586 — Critical (CVSS 10.0): SandboxJS is a JavaScript sandboxing library. Prior to 0.8.29, a sandbox escape is possible by shadowing hasOwnProperty…
CVE-2026-25520 — Critical (CVSS 10.0): SandboxJS is a JavaScript sandboxing library. Prior to 0.8.29, The return values of functions aren't wrapped.…
CVE-2025-20265 — Critical (CVSS 10.0): A vulnerability in the RADIUS subsystem implementation of Cisco Secure Firewall Management Center (FMC) Software could…
CVE-2025-20337 — Critical (CVSS 10.0): A vulnerability in a specific API of Cisco ISE and Cisco ISE-PIC could allow an unauthenticated, remote attacker to…
CVE-2025-20281 — Critical (CVSS 10.0): A vulnerability in a specific API of Cisco ISE and Cisco ISE-PIC could allow an unauthenticated, remote attacker to…
CVE-2024-42472 — Critical (CVSS 10.0): Flatpak is a Linux application sandboxing and distribution framework. Prior to versions 1.14.0 and 1.15.10, a malicious…

Browse all CWE-74 (Improper Neutralization of Special Elements (Injection)) vulnerabilities →