V1600d FirmwareOperating system · Vsolcn

CVE-2020-29375

HIGH · 8.8 CVSS v3.1 Published 2020-11-29
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
94/100
Remediation priority · Urgent
Remotely reachable Zero-click

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
An issue was discovered on V-SOL V1600D V2.03.69 and V2.03.57, V1600D4L V1.01.49, V1600D-MINI V1.01.48, V1600G1 V2.0.7 and V1.9.7, and V1600G2 V1.1.4 OLT devices. An low-privileged (non-admin) attacker can use a hardcoded password (4ef9cea10b2362f15ba4558b1d5c081f) to create an admin user.

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

V-SOL OLT devices contain a hardcoded password (4ef9cea10b2362f15ba4558b1d5c081f) embedded in the firmware that allows any authenticated user, even with low privileges, to create administrator accounts by leveraging this credential during user creation operations.

MitigationUpdate to patched firmware versions when available from V-SOL; if no patch exists, implement compensating controls such as network segmentation, strict access controls, and monitoring for unauthorized admin account creation.

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
V1600d FirmwareOperating system
Affected:= 2.03.57= 2.03.69
V1600d4l FirmwareOperating system
Affected:= 1.01.49
V1600d Mini FirmwareOperating system
Affected:= 1.01.48
V1600g1 FirmwareOperating system
Affected:= 1.9.7= 2.0.7
V1600g2 FirmwareOperating system
Affected:= 1.1.4

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

CVSS:3.1/AV:N/AC:L/PR:L/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 checks

Work through these to decide whether this CVE applies to you.

  1. Identify device model
    Log into the V-SOL OLT device and check the model name (V1600d, V1600d4l, V1600d Mini, V1600g1, or V1600g2) in the system information or device status page
    Affected if The device model is one of: V1600d, V1600d4l, V1600d Mini, V1600g1, or V1600g2
  2. Check firmware version
    Navigate to the firmware or system version section in the device web interface or run 'show version' command via CLI to retrieve the installed firmware version
    Affected if The firmware version matches any of these: 2.03.57, 2.03.69, 1.01.49, 1.01.48, 1.9.7, 2.0.7, or 1.1.4
  3. Inspect for hardcoded password in firmware/config
    Extract the configuration file or firmware image and search for the string '4ef9cea10b2362f15ba4558b1d5c081f' using a hex editor or grep utility
    Affected if The hardcoded password hash is found in the firmware or configuration files
  4. Review user account list for unauthorized admins
    Access the user management or account list section of the web interface and enumerate all accounts with administrator privileges
    Affected if There are administrator accounts that were not created by known legitimate administrators
  5. Audit user creation logs
    Check system logs, audit logs, or user management logs for user creation events, especially those performed by low-privilege accounts
    Affected if User creation operations were performed using the hardcoded credential or by accounts lacking proper authorization

You are affected if your V-SOL OLT device model is in the affected list and your firmware version matches any of the specified versions, and the hardcoded password or unauthorized admin accounts are present.

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

Update to patched firmware versions when available from V-SOL; if no patch exists, implement compensating controls such as network segmentation, strict access controls, and monitoring for unauthorized admin account creation.

Fix this in V1600d Firmware Scoped from the published advisory
  • Consultation8.0 h
  • Implementation4.0 h
  • Testing6.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,940
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $6,304.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2020-29375 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2020-29375 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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
  • No spam, self-promotion, credentials, or personal data