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Possible admin-level access to backoffice without authentication under rare conditions

High
nikolajlauridsen published GHSA-h8wc-r4jh-mg7m Jul 13, 2023

Package

nuget Umbraco.Cms (NuGet)

Affected versions

> 9.0.0

Patched versions

10.6.1, 11.4.2, 12.0.1

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.

Explanation of the vulnerability

We consider this issue a high-severity vulnerability as attackers may be able to temporarily make the configured database unavailable to Umbraco.

This is not a vulnerability in itself, but if Umbraco is restarted, while the database is unavailable, it will boot into installation mode.

When this happens, and the attacker successfully can re-establish the connection between Umbraco and the database, it will be possible to reset the admin credentials and then log in as an administrator.

Severity

High

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
High
Privileges required
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

CVE ID

CVE-2023-37267

Weaknesses

No CWEs

Credits