CVE-2026-21891
CRITICAL EPSS 80.0%
Published Jan 8, 20265mo ago · Modified Jun 17, 20261w ago
9.8 CVSS 3.1
Published Jan 8, 2026 5mo ago
Last Modified Jun 17, 2026 1w ago
Description
ZimaOS is a fork of CasaOS, an operating system for Zima devices and x86-64 systems with UEFI. In versions up to and including 1.5.0, the application checks the validity of the username but appears to skip, misinterpret, or incorrectly validate the password when the provided username matches a known system service account. The application's login function fails to properly handle the password validation result for these users, effectively granting authenticated access to anyone who knows one of these common usernames and provides any password. As of time of publication, no known patched versions are available.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability High
Threat Intelligence
EPSS Exploit Probability
80.0% percentile
Exploit & Patch Status
Public Exploit Known
No Patch Available
Weaknesses 1
CWE-287 Improper Authentication Authentication
Affected Products 1
| Vendor | Product | Version | Range |
|---|---|---|---|
| zimaspace | zimaos | * | ≤1.5.0 |
References 1
- github.com https://github.com/IceWhaleTech/ZimaOS/security/advisories/GHSA-xj93-qw9p-jxq4
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.