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CVE-2018-3875: Samsung Sth Eth 250 Firmware: Buffer overflow

CVE-2018-3875 is rated critical with a CVSS v3.1 base score of 9.9 and affects Samsung Sth Eth 250 Firmware. Per its scoring, it can be exploited over the network, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

An exploitable buffer overflow vulnerability exists in the credentials handler of video-core's HTTP server of Samsung SmartThings Hub STH-ETH-250-Firmware version 0.20.17. The video-core process incorrectly extracts fields from a user-controlled JSON payload, leading to a buffer overflow on the stack. The strncpy overflows the destination buffer, which has a size of 2,000 bytes. An attacker can send an arbitrarily long "sessionToken" value in order to exploit this vulnerability.

Severity breakdown

CVSS v3.1 9.9: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/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: Low. A basic user account is enough.
  • User interaction: None. No action from any user is needed.
  • Scope: Changed. Impact reaches beyond the vulnerable component to other resources.
  • 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-119: Improper Restriction of Operations within the Bounds of a Memory Buffer

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary.

Affected products

  • Samsung Sth Eth 250 Firmware: 0.20.17

References