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CVE-2017-3792: Cisco Telepresence Mcu Software: Authentication bypass

CVE-2017-3792 is rated critical with a CVSS v3.0 base score of 9.8 and NVD lists Cisco Telepresence Mcu Software as the affected product. 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 a proprietary device driver in the kernel of Cisco TelePresence Multipoint Control Unit (MCU) Software could allow an unauthenticated, remote attacker to execute arbitrary code or cause a denial of service (DoS) condition. The vulnerability is due to improper size validation when reassembling fragmented IPv4 or IPv6 packets. An attacker could exploit this vulnerability by sending crafted IPv4 or IPv6 fragments to a port receiving content in Passthrough content mode. An exploit could allow the attacker to overflow a buffer. If successful, the attacker could execute arbitrary code or cause a DoS condition on the affected system. Cisco TelePresence MCU platforms TelePresence MCU 5300 Series, TelePresence MCU MSE 8510 and TelePresence MCU 4500 are affected when running software version 4.3(1.68) or later configured for Passthrough content mode. Cisco has released software updates that address this vulnerability. Workarounds that address this vulnerability are not available, but mitigations are available. Cisco Bug IDs: CSCuu67675.

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.

Affected products

  • Cisco Telepresence Mcu Software: 4.3_\(1.68\); 4.3_\(2.18\); 4.3_\(2.30\); 4.3_\(2.32\); 4.4_\(3.42\); 4.4_\(3.49\); 4.4_\(3.54\); 4.4_\(3.57\); 4.4_\(3.67\); 4.5_\(1.45\); 4.5_\(1.55\); 4.5_\(1.71\)

References