Quantum Secular Labs / Blog / Advisories

CVE-2018-7183: Ntp: Buffer overflow

CVE-2018-7183 is rated critical with a CVSS v3.0 base score of 9.8 and affects Ntp, along with 3 other products in NVD’s configuration data. 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.

Vulnerability description

Buffer overflow in the decodearr function in ntpq in ntp 4.2.8p6 through 4.2.8p10 allows remote attackers to execute arbitrary code by leveraging an ntpq query and sending a response with a crafted array.

Severity breakdown

CVSS v3.0 9.8: CVSS:3.0/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-787: Out-of-bounds Write

The product writes data past the end, or before the beginning, of the intended buffer.

Affected products

Ntp: 4.2.8 p10; 4.2.8 p6; 4.2.8 p7; 4.2.8 p8; 4.2.8 p9
Freebsd: 10.3; 10.4; 11.1
Canonical Ubuntu Linux: 12.04; 14.04; 16.04; 17.10; 18.04
Netapp Element Software: all versions listed by NVD