How severe is CVE-2022-35508?

CVE-2022-35508 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2022-35508 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-35508?

CVE-2022-35508 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-2022-35508?

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

When was CVE-2022-35508 published?

CVE-2022-35508 was published on 2022-12-04 and last updated on 2026-06-17.

CVE-2022-35508

CVE-2022-35508 is a critical-severity vulnerability in Proxmox Proxmox Mail Gateway with a CVSS 3.x base score of 9.8. 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-918.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (64th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-918
Affected product: Proxmox Proxmox Mail Gateway
Published: 2022-12-04
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2022-35508?: 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.
How severe is CVE-2022-35508?: CVE-2022-35508 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2022-35508 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-35508?: CVE-2022-35508 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-2022-35508?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2022-35508 published?: CVE-2022-35508 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:-:*:*:*:*:*:*:*

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