How severe is CVE-2018-4852?

CVE-2018-4852 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-4852 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-4852?

CVE-2018-4852 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-2018-4852?

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

When was CVE-2018-4852 published?

CVE-2018-4852 was published on 2018-07-03 and last updated on 2026-06-17.

CVE-2018-4852

CVE-2018-4852 is a critical-severity vulnerability in Siemens Siclock Tc400 Firmware with a CVSS 3.x base score of 9.8. 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: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (85th 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 network access to the device could potentially circumvent the authentication mechanism if he/she is able to obtain certain knowledge specific to the attacked device.

Frequently asked questions

What is CVE-2018-4852?: A vulnerability has been identified in SICLOCK TC100 (All versions) and SICLOCK TC400 (All versions). An attacker with network access to the device could potentially circumvent the authentication mechanism if he/she is able to obtain certain knowledge specific to the attacked device.
How severe is CVE-2018-4852?: CVE-2018-4852 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-4852 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-4852?: CVE-2018-4852 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-2018-4852?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2018-4852 published?: CVE-2018-4852 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-2018-4854 — 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…
CVE-2018-4856 — Medium (CVSS 4.9): A vulnerability has been identified in SICLOCK TC100 (All versions) and SICLOCK TC400 (All versions). An attacker with…

All CVEs affecting Siemens Siclock Tc400 Firmware →

Other CWE-287 (Improper Authentication) vulnerabilities

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CVE-2026-20182 — Critical (CVSS 10.0): May 2026: This security advisory provides the details and fix information for a vulnerability that was discovered and…

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