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CVE-2016-4002: Qemu: Buffer overflow

CVE-2016-4002 is rated critical with a CVSS v3.1 base score of 9.8 and affects Qemu, 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 mipsnet_receive function in hw/net/mipsnet.c in QEMU, when the guest NIC is configured to accept large packets, allows remote attackers to cause a denial of service (memory corruption and QEMU crash) or possibly execute arbitrary code via a packet larger than 1514 bytes.

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-120: Buffer Copy without Checking Size of Input

The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer.

Affected products

Qemu: up to and including 2.6.2
Fedoraproject: 22; 23; 24
Canonical Ubuntu Linux: 12.04; 14.04; 15.10; 16.04
Debian Linux: 8.0