CyberSecBulletin
CVE-2023-50363NVD status: Modified

QTS: Improper Authorization

CVE-2023-50363 is a high-severity improper authorization vulnerability in QTS from QNAP, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists version 5.1.6.2722 build 20240402 as the first without the flaw, so updating QTS to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.42% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update QTS to 5.1.6.2722 build 20240402 or a later version.
  2. Update QuTS hero to h5.1.6.2734 build 20240414 or a later version.
  3. Read the advisory on qnap.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
QNAPQTS5.1.x up to, but not including, 5.1.6.2722 build 202404025.1.6.2722 build 20240402
QNAPQuTS heroh5.1.x up to, but not including, h5.1.6.2734 build 20240414h5.1.6.2734 build 20240414

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
NetworkCan be exploited remotely over a network, including the internet.
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
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
NoneAvailability is not affected.

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

Scoring systemScoreSeverityScored by
CVSS 3.17.4HighCNA (qnapsecurity.com.tw)
CVSS 3.18.1HighNVD

Official description

An incorrect authorization vulnerability has been reported to affect several QNAP operating system versions. If exploited, the vulnerability could allow authenticated users to bypass intended access restrictions via a network. We have already fixed the vulnerability in the following versions: QTS 5.1.6.2722 build 20240402 and later QuTS hero h5.1.6.2734 build 20240414 and later

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

The underlying weakness: Improper Authorization

The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action.

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 you perform access control checks related to your business logic. These checks may be different than the access control checks that you apply 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 Improper Authorization vulnerabilities (CWE-285)

Timeline

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

References

Other vulnerabilities in QTS

All QTS vulnerabilities

Recent Improper Authorization vulnerabilities

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