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CVE-2023-31997NVD status: Modified

UniFi OS: Incorrect Authorization

CVE-2023-31997 is a critical-severity incorrect authorization vulnerability in UniFi OS from Ubiquiti, with a CVSS 3.1 base score of 9.0 out of 10. It can be exploited from the same local network by an attacker with a low-privileged account, without any action from a user. Affected UniFi OS versions: 3.1.13 and earlier; 3.1 through 3.1.13. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.25% chance of exploitation within 30 days, which is low compared with other CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of UniFi OS you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on community.ui.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
UbiquitiUniFi OS3.1.13 and earlier; 3.1 through 3.1.13Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
AdjacentThe attacker must be on the same local network segment.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H. Scored by NVD.

Official description

UniFi OS 3.1 introduces a misconfiguration on consoles running UniFi Network that allows users on a local network to access MongoDB. Applicable Cloud Keys that are both (1) running UniFi OS 3.1 and (2) hosting the UniFi Network application. "Applicable Cloud Keys" include the following: Cloud Key Gen2 and Cloud Key Gen2 Plus.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Incorrect Authorization

The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.

How developers prevent this class of flaw

  • Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) to enforce the roles at the appropriate boundaries. Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
  • Ensure that access control checks are performed related to the business logic. These checks may be different than the access control checks that are applied to more generic resources such as files, connections, processes, memory, and database records. For example, a database may restrict access for medical records to a specific database user, but each record might only be intended to be accessible to the patient and the patient's doctor.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using authorization frameworks such as the JAAS Authorization Framework and the OWASP ESAPI Access Control feature.

More Incorrect Authorization vulnerabilities (CWE-863)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Incorrect Authorization vulnerabilities

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