CVE-2011-4514
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 · uneditedThe TELNET daemon in Siemens WinCC flexible 2004, 2005, 2007, and 2008; WinCC V11 (aka TIA portal); the TP, OP, MP, Comfort Panels, and Mobile Panels SIMATIC HMI panels; WinCC V11 Runtime Advanced; and WinCC flexible Runtime does not perform authentication, which makes it easier for remote attackers to obtain access via a TCP session.
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 confidenceThe TELNET daemon in Siemens WinCC flexible (2004-2008), WinCC V11, various SIMATIC HMI panels (TP, OP, MP, Comfort, Mobile), and WinCC Runtime products lacks authentication, allowing remote attackers to establish TCP sessions and gain unauthorized system access without any credentials.
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= 2004= 2005= 2007= 2008= v11= comfort_panels= mobile_panels= mp= op= tp= v11all versionsCVSS 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
- Authentication
- None
- Confidentiality
- Complete
- Integrity
- Complete
- Availability
- Complete
AV:N/AC:L/Au:N/C:C/I:C/A:C
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 checksWork through these to decide whether this CVE applies to you.
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Identify installed Siemens HMI/SCADA productCheck the installed programs on the system for Siemens WinCC Flexible, WinCC V11, Simatic HMI panels, or WinCC Runtime. Look in Programs and Features (Windows) or check the installation directory for Siemens software.Affected if The installed product matches any of: WinCC Flexible 2004, 2005, 2007, or 2008; WinCC V11; Comfort panels, Mobile panels, MP, OP, or TP panels; WinCC Runtime Advanced V11; or any version of WinCC Flexible Runtime.
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Verify TELNET service statusOpen Windows Services console (services.msc) and look for the TELNET service or any service related to the Siemens HMI TELNET daemon. Alternatively, run 'sc query' or check process list for telnet.exe processes.Affected if The TELNET service is running or set to start automatically.
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Check for open TELNET portOpen Command Prompt and run 'netstat -an | findstr :23' to see if port 23 is listening. Also check with 'netstat -ab' for process binding to port 23.Affected if Port 23 is listening and bound to a Siemens-related service or telnet.exe.
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Test TELNET authentication requirementAttempt a TELNET connection to localhost port 23 or the affected device IP address using 'telnet <target> 23'. Observe whether access is granted without prompting for credentials.Affected if TELNET connection succeeds and provides shell or system access without requiring any username or password.
If any affected Siemens product is installed with TELNET service running and port 23 exposed, the system is vulnerable to unauthenticated remote access.
Generated from the published advisory. Verify against your own configuration.
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 dataIsolate affected HMI and SCADA devices behind network firewalls with strict access controls, and disable the unauthenticated TELNET service on all affected systems as the CVSS 10 score indicates critical severity requiring immediate remediation.
- Consultation2.0 h
- Implementation4.0 h
- Testing2.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2011-4514 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2011-4514 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- 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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