Siemens SIPROTEC 4, SIPROTEC Compact, DIGSI 4, and EN100 Ethernet Module Inadequate Encryption Strength (CVE-2018-4839)

medium Tenable OT Security Plugin ID 500087


The remote OT asset is affected by a vulnerability.


A vulnerability has been identified in DIGSI 4 (All versions < V4.92), EN100 Ethernet module DNP3 variant (All versions < V1.05.00), EN100 Ethernet module IEC 104 variant (All versions), EN100 Ethernet module IEC 61850 variant (All versions < V4.30), EN100 Ethernet module Modbus TCP variant (All versions), EN100 Ethernet module PROFINET IO variant (All versions), Other SIPROTEC 4 relays (All versions), Other SIPROTEC Compact relays (All versions), SIPROTEC 4 7SD80 (All versions < V4.70), SIPROTEC 4 7SJ61 (All versions < V4.96), SIPROTEC 4 7SJ62 (All versions < V4.96), SIPROTEC 4 7SJ64 (All versions < V4.96), SIPROTEC 4 7SJ66 (All versions < V4.30), SIPROTEC Compact 7SJ80 (All versions < V4.77), SIPROTEC Compact 7SK80 (All versions < V4.77). An attacker with local access to the engineering system or in a privileged network position and able to obtain certain network traffic could possibly reconstruct access authorization passwords. This plugin only works with Tenable.ot. Please visit for more information.


The following text was originally created by the Cybersecurity and Infrastructure Security Agency (CISA). The original can be found at

Siemens has provided the following updates for mitigations:

- DIGSI 4: Update to v4.92.
- EN100 Ethernet module IEC 61850 variant: Update to v4.30.

- EN100 Ethernet module DNP3 variant: Update to v4.30 and configure DIGSI 4 connection password.

- SIPROTEC Compact 7SJ80: Update to v4.77.
- SIPROTEC Compact 7SK80: Update to v4.77.
- SIPROTEC 4 7SJ61, 7SJ62, and 7SJ64: Update to v4.96.
- SIPROTEC 4 7SJ66: Update to v4.30.
- SIPROTEC 4 7SD80: Update to v4.70.

As a general security measure, Siemens strongly recommends protecting network access to devices with appropriate mechanisms. To operate the devices in a protected IT environment, Siemens recommends configuring the environment according to Siemens operational guidelines for Industrial Security and following the recommendations in the product manuals.

Recommended security guidelines to secure substations and defense in depth can be found at:

For more information on these vulnerabilities and associated software updates, please see Siemens security advisory SSA-203306

See Also

Plugin Details

Severity: Medium

ID: 500087

Version: 1.3

Type: remote

Family: Tenable.ot

Published: 2/7/2022

Updated: 7/24/2023

Risk Information


Risk Factor: Low

Score: 3.6


Risk Factor: Low

Base Score: 3.5

Vector: CVSS2#AV:N/AC:M/Au:S/C:P/I:N/A:N

CVSS Score Source: CVE-2018-4839


Risk Factor: Medium

Base Score: 5.3

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

Vulnerability Information

CPE: cpe:/o:siemens:siprotec_compact_7sj80_firmware, cpe:/o:siemens:siprotec_compact_7sk80_firmware, cpe:/o:siemens:siprotec_4_7sj66_firmware, cpe:/o:siemens:digsi_4, cpe:/o:siemens:en100_ethernet_module_iec_104_firmware:-, cpe:/o:siemens:en100_ethernet_module_dnp3_firmware:-, cpe:/o:siemens:en100_ethernet_module_modbus_tcp_firmware:-, cpe:/o:siemens:en100_ethernet_module_profinet_io_firmware:-, cpe:/o:siemens:en100_ethernet_module_iec_61850_firmware

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 3/8/2018

Vulnerability Publication Date: 3/8/2018

Reference Information

CVE: CVE-2018-4839

CWE: 326