PSA-2026-00090: Proxmox Mail Gateway: XSS in content-type display in quarantine views
This Proxmox advisory covers a security issue in Proxmox Mail Gateway.
Key facts
- Fixed in
- pmg-gui 5.2.4
- Advisory id
- PSA-2026-00090
- Source published
- Listed by VulniPulse
Compiled by VulniPulse from the linked sources. How records are collected and checked.
Affected products & platforms
Description
The Filetype field in the AttachementGrid component shown in the quarantine views takes the data from the Content-Type header of the quarantined mail. The display field was not HTML-encoded allowing for an attacker to launch an XSS attack by sending a mail with prepared attachments.
The issue was found internally. Packages: pmg-gui.
Affected product named by the advisory: Proxmox Mail Gateway.
Text from the source record.
Fix and mitigation
Upgrade to a fixed release named by Proxmox:
- pmg-gui 5.2.4
Vendor guidance
- Update to the fixed package versions: pmg-gui >= 5.2.4.
Support dates for the fixed release lines
- Proxmox Mail Gateway 5: support ended
More Proxmox advisories
CVE-2026-116264Nov 10, 2026Proxmox Mail Gateway: Several issues in libmime-tools-perlPSA-2026-00089Nov 10, 2026Proxmox: Several issues in libpve-http-server-perlPSA-2026-00065Oct 7, 2026Proxmox Mail Gateway: Bypass DMARC check by spoofed envelope sender headerPSA-2026-00064Oct 7, 2026Proxmox Mail Gateway: Administrator to root privilege escalationPSA-2026-00063Oct 7, 2026Proxmox Mail Gateway: Administrator to root privilege escalationPSA-2026-00099Nov 10, 2026Proxmox: Incomplete validation of UPID when handling "stop task" API requests
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