How severe is CVE-2018-4856?

CVE-2018-4856 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2018-4856 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-4856?

CVE-2018-4856 primarily affects Siemens Siclock Tc400 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-4856?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2018-4856 published?

CVE-2018-4856 was published on 2018-07-03 and last updated on 2026-06-17.

CVE-2018-4856

CVE-2018-4856 is a medium-severity vulnerability in Siemens Siclock Tc400 Firmware with a CVSS 3.x base score of 4.9. 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-287.

Key facts

Severity: Medium (CVSS 3.x base score 4.9)
CVSS v2: 4.0
EPSS exploit prediction: 1% (67th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Siemens Siclock Tc400 Firmware
Published: 2018-07-03
Last modified: 2026-06-17

Description

A vulnerability has been identified in SICLOCK TC100 (All versions) and SICLOCK TC400 (All versions). An attacker with administrative access to the device's management interface could lock out legitimate users. Manual interaction is required to restore the access of legitimate users.

Frequently asked questions

What is CVE-2018-4856?: A vulnerability has been identified in SICLOCK TC100 (All versions) and SICLOCK TC400 (All versions). An attacker with administrative access to the device's management interface could lock out legitimate users. Manual interaction is required to restore the access of legitimate users.
How severe is CVE-2018-4856?: CVE-2018-4856 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2018-4856 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-4856?: CVE-2018-4856 primarily affects Siemens Siclock Tc400 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-4856?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-4856 published?: CVE-2018-4856 was published on 2018-07-03 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:o:siemens:siclock_tc400_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:siemens:siclock_tc100_firmware:-:*:*:*:*:*:*:*

More vulnerabilities in Siemens Siclock Tc400 Firmware

CVE-2018-4853 — Critical (CVSS 9.8): A vulnerability has been identified in SICLOCK TC100 (All versions) and SICLOCK TC400 (All versions). An attacker with…
CVE-2018-4852 — Critical (CVSS 9.8): A vulnerability has been identified in SICLOCK TC100 (All versions) and SICLOCK TC400 (All versions). An attacker with…
CVE-2018-4854 — High (CVSS 8.8): A vulnerability has been identified in SICLOCK TC100 (All versions) and SICLOCK TC400 (All versions). An attacker with…
CVE-2018-4851 — High (CVSS 8.2): A vulnerability has been identified in SICLOCK TC100 (All versions) and SICLOCK TC400 (All versions). An attacker with…
CVE-2018-4855 — Medium (CVSS 6.5): A vulnerability has been identified in SICLOCK TC100 (All versions) and SICLOCK TC400 (All versions). Unencrypted…

All CVEs affecting Siemens Siclock Tc400 Firmware →

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