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CVE-2017-8410: D-Link Dcs 1100 Firmware: Buffer overflow

CVE-2017-8410 is rated critical with a CVSS v3.1 base score of 9.8 and NVD lists 2 affected products, including D-Link Dcs 1100 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

An issue was discovered on D-Link DCS-1100 and DCS-1130 devices. The binary rtspd in /sbin folder of the device handles all the rtsp connections received by the device. It seems that the binary performs a memcpy operation at address 0x00011E34 with the value sent in the "Authorization: Basic" RTSP header and stores it on the stack. The number of bytes to be copied are calculated based on the length of the string sent in the RTSP header by the client. As a result, memcpy copies more data then it can hold on stack and this results in corrupting the registers for the caller function sub_F6CC which results in memory corruption. The severity of this attack is enlarged by the fact that the same value is then copied on the stack in the function 0x00011378 and this allows to overflow the buffer allocated and thus control the PC register which will result in arbitrary code execution on the device.

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-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

  • D-Link Dcs 1100 Firmware: all versions listed by NVD
  • D-Link Dcs 1130 Firmware: all versions listed by NVD

References