CVE-2026-21891 (GCVE-0-2026-21891)
Vulnerability from cvelistv5
Published
2026-01-08 14:00
Modified
2026-01-08 15:55
Severity ?
CWE
  • CWE-287 - Improper Authentication
Summary
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.
Impacted products
Vendor Product Version
IceWhaleTech ZimaOS Version: <= 1.5.0
Create a notification for this product.
Show details on NVD website


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