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Ncp Secure Entry ClientApplication · Ncp E

CVE-2017-17023

HIGH · 8.1 CVSS v3.0 Published 2019-04-09
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
90/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

The Sophos IPSec Client 11.04 (rebranded NCP Secure Entry Client) has a vulnerability in its software update mechanism where update metadata is fetched over insecure HTTP without cryptographic signature verification, allowing MITM/MOTS attackers to inject and execute arbitrary malicious code on target systems.

MitigationDisable automatic updates for the affected VPN client and implement network-level controls to block untrusted update connections until a patched version from Sophos or NCP is available; consider alternative VPN solutions if vendor patches are unavailable.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Ncp Secure Entry ClientApplication
Affected:= 10.11
Ipsec ClientApplication
Affected:= 11.04

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify installed VPN client
    Check system for Sophos IPSec Client or NCP Secure Entry Client installation by reviewing installed programs in system settings or program directories
    Affected if Either Sophos IPSec Client or NCP Secure Entry Client is present on the system
  2. Determine installed version
    Locate the installed version of the VPN client through program properties, about dialog, or version file within the application directory
    Affected if Version matches 10.11 for NCP Secure Entry Client or 11.04 for Sophos IPSec Client
  3. Verify automatic update configuration
    Access the VPN client settings or configuration panel to determine whether automatic update checks are enabled
    Affected if Automatic updates are enabled and the client is set to check for updates automatically
  4. Inspect update connection protocol
    Review network traffic configuration or proxy settings within the VPN client to verify whether HTTP (unencrypted) connections are permitted for update metadata retrieval
    Affected if The client is configured to allow unencrypted HTTP connections for update metadata without requiring signature verification

A user is affected if they have version 10.11 of NCP Secure Entry Client or version 11.04 of Sophos IPSec Client installed with automatic updates enabled and HTTP connections permitted for the update mechanism.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Disable automatic updates for the affected VPN client and implement network-level controls to block untrusted update connections until a patched version from Sophos or NCP is available; consider alternative VPN solutions if vendor patches are unavailable.

Fix this in Ncp Secure Entry Client Scoped from the published advisory
  • Consultation6.0 h
  • Implementation12.0 h
  • Testing6.0 h
  • Review / QA4.0 h
28.0 hours of engineering $4,980
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2017-17023 in production — separate from our analysis above.

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What this is

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What belongs here
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