CVE-2021-28912
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 · uneditedBAB TECHNOLOGIE GmbH eibPort V3. Each device has its own unique hard coded and weak root SSH key passphrase known as 'eibPort string'. This is usable and the final part of an attack chain to gain SSH root access.
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 BAB TECHNOLOGIE GmbH eibPort V3 contains a hardcoded and weak root SSH key passphrase (known as the 'eibPort string') that provides SSH root access to the device. This is a backdoor vulnerability where the credentials are hardcoded into the firmware and are not changeable through normal configuration.
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< 3.9.1CVSS 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
- High
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
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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Confirm eibPort device model and SSH availabilityIdentify the device as BAB TECHNOLOGIE GmbH eibPort V3 and check if SSH service is enabled or accessible on the device (typically port 22)Affected if The device is an eibPort V3 and SSH is reachable on the network
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Check installed firmware versionAccess the device web interface or use the vendor-provided method to retrieve the current firmware version installed on the eibPort V3Affected if The firmware version is below 3.9.1 (for example, 3.9.0, 3.8.x, or earlier)
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Verify hardcoded SSH credentials are activeAttempt SSH root login to the device using the hardcoded 'eibPort string' passphrase known for this CVE. If the login succeeds, the backdoor credentials are functional.Affected if SSH authentication succeeds with the hardcoded passphrase, confirming the backdoor is present and exploitable
You are affected if you have an eibPort V3 device with SSH accessible and firmware version lower than 3.9.1, where the hardcoded root SSH passphrase grants unauthorized 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.
dbcve · scoped3.9.1
Disable remote SSH access where possible, change default credentials if configurable, apply vendor firmware updates, and restrict network access to the eibPort devices.
EibPort Firmware 3.9.1 or later
- 1. Backup current device configuration before firmware upgrade
- 2. Download EibPort Firmware version 3.9.1 or later from the official BAB TECHNOLOGIE GmbH vendor source
- 3. Upload and install the firmware update through the device's web interface or management console
- 4. After upgrade, immediately change the default SSH root credentials to a strong, unique password
- 5. Verify SSH access works with the new credentials
- 6. Consider implementing key-based authentication and disabling password-based root SSH access if not needed
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation4.0 h
- Implementation8.0 h
- Testing4.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,120.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-28912 — 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-2021-28912 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
- No spam, self-promotion, credentials, or personal data