CVE-2017-17023 - Improper Access Control vulnerability in NCP E and Sophos products

Publication

2019-04-09

Last modification

2019-04-11

Summary

The Sophos UTM VPN endpoint interacts with client software provided by NPC Engineering (www.ncp-e.com). The affected client software, "Sophos IPSec Client" 11.04 is a rebranded version of NCP "Secure Entry Client" 10.11 r32792. A vulnerability in the software update feature of the VPN client allows a man-in-the-middle (MITM) or man-on-the-side (MOTS) attacker to execute arbitrary, malicious software on a target user's computer. This is related to SIC_V11.04-64.exe (Sophos), NCP_EntryCl_Windows_x86_1004_31799.exe (NCP), and ncpmon.exe (both Sophos and NCP). The vulnerability exists because: (1) the VPN client requests update metadata over an insecure HTTP connection; and (2) the client software does not check if the software update is signed before running it.

Classification

CWE-284 - Improper Access Control

Risk level (CVSS AV:N/AC:M/Au:N/C:C/I:C/A:C)

High

9.3

Access Vector

  • Network
  • Adjacent Network
  • Local

Access Complexity

  • Low
  • Medium
  • High

Authentication

  • None
  • Single
  • Multiple

Confident. Impact

  • Complete
  • Partial
  • None

Integrity Impact

  • Complete
  • Partial
  • None

Affected Products