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CVE-2018-0304: A vulnerability in the Cisco Fabric Services component of Cisco FXOS Software and Cisco NX-OS Software could…

CVE-2018-0304 is rated critical with a CVSS v3.0 base score of 9.8 and NVD lists 5 affected products, including Cisco Nexus 7000 Firmware. 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

A vulnerability in the Cisco Fabric Services component of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated, remote attacker to read sensitive memory content, create a denial of service (DoS) condition, or execute arbitrary code as root. The vulnerability exists because the affected software insufficiently validates Cisco Fabric Services packet headers. An attacker could exploit this vulnerability by sending a crafted Cisco Fabric Services packet to an affected device. A successful exploit could allow the attacker to cause a buffer overflow or buffer overread condition in the Cisco Fabric Services component, which could allow the attacker to read sensitive memory content, create a DoS condition, or execute arbitrary code as root. This vulnerability affects the following if configured to use Cisco Fabric Services: Firepower 4100 Series Next-Generation Firewalls, Firepower 9300 Security Appliance, MDS 9000 Series Multilayer Switches, Nexus 2000 Series Fabric Extenders, Nexus 3000 Series Switches, Nexus 3500 Platform Switches, Nexus 5500 Platform Switches, Nexus 5600 Platform Switches, Nexus 6000 Series Switches, Nexus 7000 Series Switches, Nexus 7700 Series Switches, Nexus 9000 Series Switches in standalone NX-OS mode, Nexus 9500 R-Series Line Cards and Fabric Modules, UCS 6100 Series Fabric Interconnects, UCS 6200 Series Fabric Interconnects, UCS 6300 Series Fabric Interconnects. Cisco Bug IDs: CSCvd69951, CSCve02459, CSCve02461, CSCve02463, CSCve02474, CSCve04859.

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-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-125: Out-of-bounds Read

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

Affected products

  • Cisco Nexus 7000 Firmware: 7.3\(2\)d1\(0.49\); 8.0\(1\); 8.1\(0.112\)s0
  • Cisco Nexus 5000 Firmware: 7.0\(0\)hsk\(0.357\); 7.3\(0\)d1\(0.98\); 8.1\(0.2\)s0
  • Cisco Firepower 9000 Firmware: r211; r231
  • Cisco Nexus 9000 Firmware: 8.1\(0\)bd\(0.20\); 8.1\(1\)s4
  • Cisco Unified Computing System Firmware: 3.1\(3a\)a; 7.0\(0\)hsk\(0.357\)

References