CVE-2023-37267Network attack vector

Administrator access via post-restart superuser sign-in

Published Jul 13, 2023 · Updated Oct 31, 2024

Improper access control in affected Umbraco CMS releases allows remote attackers to gain backoffice administrator access after a restart. InstallApiController.CompleteInstall restarts the runtime and then signs in the superuser whenever the pre-restart runtime level is Install. Exploitation requires the rare install-state restart condition and user interaction; successful access carries full backoffice permissions.

CVSS severity7.5
High
EPSS probability0.71%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper access control in affected Umbraco CMS releases allows remote attackers to gain backoffice administrator access after a restart. InstallApiController.CompleteInstall restarts the runtime and then signs in the superuser whenever the pre-restart runtime level is Install. Exploitation requires the rare install-state restart condition and user interaction; successful access carries full backoffice permissions.

The record

CVE
CVE-2023-37267
Published
Jul 13, 2023
Updated
Oct 31, 2024
Vendor
Umbraco
Product
Umbraco CMS
Classifications
CWE-284, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 13, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 31, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 11.0.0, < 11.4.2
  2. Affected versionversion== 12.0.0
  3. Affected versionversion=>= 9.0.0, < 10.6.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Umbraco · Umbraco CMSversion=>= 11.0.0, < 11.4.2; version== 12.0.0; version=>= 9.0.0, < 10.6.1

Published CVSS scores

9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5GitHubCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-284Improper Access Control
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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