CVE-2026-28798 CRITICAL

CVE-2026-28798: Arbitrary internal service access via /v1/sys/proxy when Cloudflare Tunnel is enabled on ZimaOS

Vendor Icewhaletech
Product ZimaOS
Weakness CWE-918 · SSRF
Published April 3, 2026
Last update April 6, 2026
View on NVD All CVEs

CVSS base score

9.1/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Confidentiality High
Integrity High

CVSS vector

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

What the vulnerability does

01Description

ZimaOS is a fork of CasaOS, an operating system for Zima devices and x86-64 systems with UEFI. Prior to version 1.5.3, a proxy endpoint (/v1/sys/proxy) exposed by ZimaOS's web interface can be abused (via an externally reachable domain using a Cloudflare Tunnel) to make requests to internal localhost services. This results in unauthenticated access to internal-only endpoints and sensitive local services when the product is reachable from the Internet through a Cloudflare Tunnel. This issue has been patched in version 1.5.3.

Key dates

02Disclosure timeline

April 3, 2026 CVE published
April 6, 2026 Record updated