Siclock Tc400 FirmwareOperating system · Siemens

CVE-2018-4855

MEDIUM · 6.5 CVSS v3.0 Published 2018-07-03
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
72/100
Remediation priority · Elevated
Remotely reachable No privileges

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
A vulnerability has been identified in SICLOCK TC100 (All versions) and SICLOCK TC400 (All versions). Unencrypted storage of passwords in the client configuration files and during network transmission could allow an attacker in a privileged position to obtain access passwords.

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

SICLOCK TC100 and TC400 time servers store access passwords in plaintext in client configuration files and transmit them unencrypted over the network, allowing privileged network attackers to intercept credentials.

MitigationImplement TLS/SSL encryption for network communications and encrypt password storage in configuration files; contact vendor for firmware updates.

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
Siclock Tc400 FirmwareOperating system
Affected:all versions
Siclock Tc100 FirmwareOperating system
Affected:all versions

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
Low
Privileges
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

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

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 Siclock time server presence
    Review installed software inventories, network device scans, or system configurations to determine if Siemens Siclock TC100 or TC400 time server hardware or firmware is deployed in the environment.
    Affected if Siclock TC100 or TC400 time server is present in the environment
  2. Locate client configuration files
    Search for client configuration files associated with the Siclock time server. These are typically stored in installation directories, config folders, or application data locations where connection credentials are saved.
    Affected if Siclock client configuration files exist on the system
  3. Inspect for plaintext passwords
    Open the located configuration files and examine them for any password fields. Look for readable text strings appearing near password-related labels (such as 'password', 'passwd', or 'pwd') that are stored in plaintext rather than encrypted or hashed.
    Affected if Configuration files contain readable, unencrypted password strings
  4. Verify network traffic encryption
    Use a network packet capture tool to monitor communications between clients and the Siclock time server. Examine whether the protocol used transmits authentication credentials in plaintext without TLS/SSL encryption.
    Affected if Network traffic between client and time server transmits credentials in cleartext without encryption

The environment is affected if Siclock TC100 or TC400 time servers are present and their configuration files store plaintext passwords or transmit credentials over the network without encryption.

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

Implement TLS/SSL encryption for network communications and encrypt password storage in configuration files; contact vendor for firmware updates.

Fix this in Siclock Tc400 Firmware Scoped from the published advisory
  • Consultation3.0 h
  • Implementation8.0 h
  • Testing4.0 h
  • Review / QA2.0 h
17.0 hours of engineering $3,000
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Scan for this in your stack

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dbcve dependency scanner

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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-2018-4855 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
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