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Not in CISA KEV
HIGH severity

CVE-2023-37267 Umbraco.Cms.Infrastructure

HIGHFix: umbraco/Umbraco-CMS@1f26f2c

CVE-2023-37267 is a high-severity (CVSS 7.5) CWE-284 vulnerability in Umbraco.Cms.Infrastructure. A fix is available for Umbraco.Cms.Infrastructure — see the affected versions and patch details below.

Umbraco allows possible Admin-level access to backoffice without Auth under rare conditions

Also known asGHSA-h8wc-r4jh-mg7m
Published
Jul 13, 2023
Updated
Aug 12, 2026
Affected
6 pkgs
Patched
6 / 6
Exploits
None indexed
Exploitation data as of Sep 23, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

  • A successful exploit gives an attacker total control of the affected component, not partial access.
  • CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2023-37267.

EPSS Exploitation Probability

via FIRST.org ↗
0.7%probability of exploitation in next 30 days
Lower Risk0.00%
Lower risk than most CVEs52th percentile — riskier than 52% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

How urgent is this, really

CVE-2023-37267 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.

Where this sits among everything scored

Of 378,156 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.

Real-World Exposure

6 pkgs affected
.NETUmbraco.Cms.Infrastructure.NETUmbraco.Cms.Infrastructure.NETUmbraco.Cms.Infrastructure.NETUmbraco.Cms.Web.BackOffice.NETUmbraco.Cms.Web.BackOffice.NETUmbraco.Cms.Web.BackOffice

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects NuGet packages — download data is not available via public APIs for these ecosystems.

Description

Under rare conditions, a restart of Umbraco can allow unauthorized users to gain admin-level permissions.

Impact

An unauthorized user gaining admin-level access and permissions to the backoffice.

Patches

10.6.1, 11.4.2, 12.0.1

Workarounds

  • Enabling the Unattended Install feature will mean the vulnerability is not exploitable.
  • Enabling IP restrictions to */install/* and */umbraco/* will limit the exposure to allowed IP addresses.

Affected Packages

6 total 6 fixed
EcosystemPackageVulnerable rangeFix
.NETNuGetUmbraco.Cms.Infrastructure9.0.0&&< 10.6.110.6.1dotnet add package Umbraco.Cms.Infrastructure --version 10.6.1
.NETNuGetUmbraco.Cms.Infrastructure11.0.0&&< 11.4.211.4.2dotnet add package Umbraco.Cms.Infrastructure --version 11.4.2
.NETNuGetUmbraco.Cms.Infrastructure12.0.0&&< 12.0.112.0.1dotnet add package Umbraco.Cms.Infrastructure --version 12.0.1
.NETNuGetUmbraco.Cms.Web.BackOffice9.0.0&&< 10.6.110.6.1dotnet add package Umbraco.Cms.Web.BackOffice --version 10.6.1
.NETNuGetUmbraco.Cms.Web.BackOffice11.0.0&&< 11.4.211.4.2dotnet add package Umbraco.Cms.Web.BackOffice --version 11.4.2
.NETNuGetUmbraco.Cms.Web.BackOffice12.0.0&&< 12.0.112.0.1dotnet add package Umbraco.Cms.Web.BackOffice --version 12.0.1

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Umbraco.Cms.Infrastructure, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

  2. Fix

    Update Umbraco.Cms.Infrastructure to 10.6.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-37267 is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2023-37267 can be triaged on real exposure rather than presence alone.

Tailored to CVE-2023-37267. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Under rare conditions, a restart of Umbraco can allow unauthorized users to gain admin-level permissions. ### Impact An unauthorized user gaining admin-level access and permissions to the backoffice. ### Patches 10.6.1, 11.4.2, 12.0.1 ### Workarounds * Enabling the [Unattended Install](https://docs.umbraco.com/umbraco-cms/reference/configuration/unattendedsettings) feature will mean the vulnerability is not exploitable. * Enabling IP restrictions to `*/install/*` and `*/umbraco/*` will limit the exposure to allowed IP addresses.
O3 Security · Impact-Aware SCA

Is CVE-2023-37267 in your dependencies?

O3 Security finds CVE-2023-37267 across NuGet dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

CVE-2023-37267: Umbraco.Cms (High 7.5) | O3 Security