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CVE-2018-15439: A vulnerability in the Cisco Small Business Switches software could allow an unauthenticated, remote…

CVE-2018-15439 is rated critical with a CVSS v3.1 base score of 9.8 and NVD lists 114 affected products, including Cisco Sg200 50 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 Small Business Switches software could allow an unauthenticated, remote attacker to bypass the user authentication mechanism of an affected device. The vulnerability exists because under specific circumstances, the affected software enables a privileged user account without notifying administrators of the system. An attacker could exploit this vulnerability by using this account to log in to an affected device and execute commands with full admin rights. Cisco has not released software updates that address this vulnerability. This advisory will be updated with fixed software information once fixed software becomes available. There is a workaround to address this vulnerability.

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-798: Use of Hard-coded Credentials

The product contains hard-coded credentials, such as a password or cryptographic key.

Affected products

  • Cisco Sg200 50 Firmware: all versions listed by NVD
  • Cisco Sg200 50p Firmware: all versions listed by NVD
  • Cisco Sg200 50fp Firmware: all versions listed by NVD
  • Cisco Sg200 26 Firmware: all versions listed by NVD
  • Cisco Sg200 26p Firmware: all versions listed by NVD
  • Cisco Sg200 26fp Firmware: all versions listed by NVD
  • Cisco Sg200 18 Firmware: all versions listed by NVD
  • Cisco Sg200 10fp Firmware: all versions listed by NVD
  • Cisco Sg200 08 Firmware: all versions listed by NVD
  • Cisco Sg200 08p Firmware: all versions listed by NVD
  • Cisco Sf200 24 Firmware: all versions listed by NVD
  • Cisco Sf200 24p Firmware: all versions listed by NVD
  • Cisco Sf200 24fp Firmware: all versions listed by NVD
  • Cisco Sf200 48 Firmware: all versions listed by NVD
  • Cisco Sf200 48p Firmware: all versions listed by NVD

References