What’s Vulnerable › Vulnerabilities

CVE-2023-37267: Umbraco allows possible Admin-level access to backoffice without Auth under rare conditions

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.7% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2023-07-13 · updated 2026-06-17
• Weakness: CWE-284

Description

Umbraco is a ASP.NET CMS. Under rare conditions a restart of Umbraco can allow unauthorized users access to admin-level permissions. This vulnerability was patched in versions 10.6.1, 11.4.2 and 12.0.1.

Affected products

• Umbraco-CMS: from 10.0.0 before 10.6.1; from 11.0.0 before 11.4.2; from 12.0.0 before 12.0.1 — fixed in 10.6.1, 11.4.2, 12.0.1

How to fix

Upgrade to a fixed version: Umbraco-CMS 10.6.1, 11.4.2, 12.0.1. Check the vendor advisory for mitigations.

References

• https://github.com/umbraco/Umbraco-CMS/commit/1f26f2c6f3428833892cde5c6d8441fb041e410e
• https://github.com/umbraco/Umbraco-CMS/commit/20a4e475c8d7b91d263e4e103ef19f3644e7b569
• https://github.com/umbraco/Umbraco-CMS/commit/82eae48d098b9deecbdf86cf288b2b18020e1fed
• https://github.com/umbraco/Umbraco-CMS/security/advisories/GHSA-h8wc-r4jh-mg7m
• https://github.com/umbraco/Umbraco-CMS/commit/1f26f2c6f3428833892cde5c6d8441fb041e410e
• https://github.com/umbraco/Umbraco-CMS/commit/20a4e475c8d7b91d263e4e103ef19f3644e7b569
• https://github.com/umbraco/Umbraco-CMS/commit/82eae48d098b9deecbdf86cf288b2b18020e1fed
• https://github.com/umbraco/Umbraco-CMS/security/advisories/GHSA-h8wc-r4jh-mg7m

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