M Bus 900s FirmwareOperating system · Piigab

CVE-2023-33868

CRITICAL · 9.8 CVSS v3.1 Published 2023-07-06
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges 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
The number of login attempts is not limited. This could allow an attacker to perform a brute force on HTTP basic authentication.

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 · moderate confidence

The affected system does not enforce any limits on login attempts for HTTP basic authentication. This allows attackers to repeatedly guess credentials without restriction, enabling brute force attacks against the authentication mechanism.

MitigationImplement rate limiting or account lockout policies on the HTTP basic authentication endpoint to restrict the number of failed login attempts within a given time window.

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
M Bus 900s 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
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/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 the device model and firmware version
    Access the device's web interface or administrative console and locate the system information or about page to confirm the device is a Piigab M Bus 900s and note the firmware version.
    Affected if The device is a Piigab M Bus 900s on any firmware version.
  2. Verify HTTP basic authentication is enabled
    Check the device's authentication settings or security configuration page to confirm that HTTP basic authentication is the configured authentication method.
    Affected if HTTP basic authentication is the active authentication mechanism.
  3. Locate authentication-related configuration files
    If SSH or console access is available, examine the device configuration files (typically in /etc, /config, or similar directories) for files related to HTTP authentication, web server settings, or security policies.
    Affected if Configuration files exist but contain no rate limiting or login attempt restriction settings.
  4. Inspect authentication logs for login attempt tracking
    Access the device's logs (via web interface, syslog, or local log files) and review failed authentication entries to determine if the system records or limits consecutive failed attempts.
    Affected if Logs show unlimited failed login attempts without any blocking or throttling behavior.
  5. Test the login endpoint for rate limiting behavior
    Send multiple HTTP basic authentication requests with invalid credentials from an external system or script and observe the response. Check if the system returns rate limiting error codes (such as 429 Too Many Requests) or blocks the IP address after a certain number of attempts.
    Affected if The system accepts unlimited authentication attempts without imposing any restrictions.

The system is affected if it is a Piigab M Bus 900s with HTTP basic authentication enabled and no rate limiting or account lockout mechanism is 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

Implement rate limiting or account lockout policies on the HTTP basic authentication endpoint to restrict the number of failed login attempts within a given time window.

Fix this in M Bus 900s Firmware Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA1.0 h
9.0 hours of engineering $1,600
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Scan for this in your stack

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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-2023-33868 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
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