cve-2026-21891

CRITICAL CVSS 9.4 opencve
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.

Timeline
Published
2026-01-08 14:15 UTC
Last Modified
2026-06-17
CVSS Details

CVSS details not available.

Affected Products

No product information available.

Weaknesses (CWE)
CVSS metrics
Version Base Severity Vector Exploitability Impact Source
3.1 9.4 CRITICAL CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L mitre
3.1 9.4 CRITICAL CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L nvd
3.1 9.4 CRITICAL CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L opencve
References

No references available.

Linked Vulnerabilities

No linked vulnerabilities found.

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Enrichment data
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