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CVE-2018-19949: QNAP NAS File Station Command Injection Vulnerability

CVE-2018-19949 is rated critical with a CVSS v3.1 base score of 9.8 and affects QNAP Network Attached Storage (NAS). Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available. CISA added it to its Known Exploited Vulnerabilities catalog on 2022-05-24, which means exploitation in the wild has been observed.

Vulnerability description

If exploited, this command injection vulnerability could allow remote attackers to run arbitrary commands. QNAP has already fixed the issue in the following QTS versions. QTS 4.4.2.1231 on build 20200302; QTS 4.4.1.1201 on build 20200130; QTS 4.3.6.1218 on build 20200214; QTS 4.3.4.1190 on build 20200107; QTS 4.3.3.1161 on build 20200109; QTS 4.2.6 on build 20200109.

Severity breakdown

CVSS v3.1 9.8: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

  • Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
  • Attack complexity: Low. No special conditions; the attack can be repeated reliably.
  • Privileges required: None. No account or prior access is needed.
  • User interaction: None. No action from any user is needed.
  • Scope: Unchanged. Impact stays within the vulnerable component.
  • Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
  • Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
  • Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-20: Improper Input Validation

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

CWE-77: Improper Neutralization of Special Elements used in a Command

The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component.

CWE-78: Improper Neutralization of Special Elements used in an OS Command

The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command before it is sent to a downstream component.

Affected products

  • QNAP Qts: before 4.2.6; from 4.3.1.0013 before 4.3.3.1161; from 4.3.4 before 4.3.4.1190; from 4.3.6 before 4.3.6.1218; from 4.4.0 before 4.4.1.1201; from 4.4.2 before 4.4.2.1231; 4.2.6; 4.2.6 build_20170517; 4.2.6 build_20190322; 4.2.6 build_20190730; 4.2.6 build_20190921; 4.2.6 build_20191107

References