How severe is CVE-2018-4838?

CVE-2018-4838 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2018-4838 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-4838?

CVE-2018-4838 primarily affects Siemens En100 Ethernet Module Iec 104 Firmware. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-4838?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2018-4838 published?

CVE-2018-4838 was published on 2018-03-08 and last updated on 2026-06-17.

CVE-2018-4838

CVE-2018-4838 is a high-severity vulnerability in Siemens En100 Ethernet Module Iec 104 Firmware with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-306.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (70th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-306
Affected product: Siemens En100 Ethernet Module Iec 104 Firmware
Published: 2018-03-08
Last modified: 2026-06-17

Description

A vulnerability has been identified in EN100 Ethernet module IEC 61850 variant (All versions < V4.30), EN100 Ethernet module DNP3 variant (All versions < V1.04), EN100 Ethernet module PROFINET IO variant (All versions), EN100 Ethernet module Modbus TCP variant (All versions), EN100 Ethernet module IEC 104 variant (All versions < V1.22). The web interface (TCP/80) of affected devices allows an unauthenticated user to upgrade or downgrade the firmware of the device, including to older versions with known vulnerabilities.

Frequently asked questions

What is CVE-2018-4838?: A vulnerability has been identified in EN100 Ethernet module IEC 61850 variant (All versions < V4.30), EN100 Ethernet module DNP3 variant (All versions < V1.04), EN100 Ethernet module PROFINET IO variant (All versions), EN100 Ethernet module Modbus TCP variant (All versions), EN100 Ethernet module IEC 104 variant (All versions < V1.22). The web interface (TCP/80) of affected devices allows an unauthenticated user to upgrade or downgrade the firmware of the device, including to older versions with known vulnerabilities.
How severe is CVE-2018-4838?: CVE-2018-4838 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2018-4838 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-4838?: CVE-2018-4838 primarily affects Siemens En100 Ethernet Module Iec 104 Firmware. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-4838?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2018-4838 published?: CVE-2018-4838 was published on 2018-03-08 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:o:siemens:en100_ethernet_module_iec_104_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:siemens:en100_ethernet_module_dnp3_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:siemens:en100_ethernet_module_modbus_tcp_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:siemens:en100_ethernet_module_profinet_io_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:siemens:en100_ethernet_module_iec_61850_firmware:*:*:*:*:*:*:*:*

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CVE-2022-30938 — High (CVSS 7.5): A vulnerability has been identified in EN100 Ethernet module DNP3 IP variant (All versions), EN100 Ethernet module IEC…
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