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Multilin B30 FirmwareOperating system · Ge

CVE-2021-27418

MEDIUM · 6.1 CVSS v3.1 Published 2022-03-23
Fix available
A fix is available. Upgrade to 8.10 or later.
See remediation →
68/100
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
GE UR firmware versions prior to version 8.1x supports web interface with read-only access. The device fails to properly validate user input, making it possible to perform cross-site scripting attacks, which may be used to send a malicious script. Also, UR Firmware web server does not perform HTML encoding of user-supplied strings.

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

GE UR (Universal Relay) firmware versions prior to 8.1x contain a reflected XSS vulnerability in the web interface. The web server fails to properly validate user input and does not perform HTML encoding of user-supplied strings, allowing authenticated users with read-only access to inject malicious scripts.

MitigationUpdate GE UR firmware to version 8.1x or later which implements proper input validation and HTML encoding. If updating is not immediately possible, minimize network exposure of the web interface and monitor for suspicious requests.

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
Multilin B30 FirmwareOperating system
Affected:< 8.10
Multilin B90 FirmwareOperating system
Affected:< 8.10
Multilin C60 FirmwareOperating system
Affected:< 8.10
Multilin C70 FirmwareOperating system
Affected:< 8.10
Multilin C95 FirmwareOperating system
Affected:< 8.10
Multilin D30 FirmwareOperating system
Affected:< 8.10
Multilin D60 FirmwareOperating system
Affected:< 8.10
Multilin F35 FirmwareOperating system
Affected:< 8.10

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
Changed
Confidentiality
Low
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/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 the GE Multilin relay model
    Check the device label, web interface login page, or system information page for the model number (B30, B90, C60, C70, C95, D30, D60, or F35)
    Affected if The model is one of B30, B90, C60, C70, C95, D30, D60, or F35 and the firmware version is below 8.10
  2. Determine the installed firmware version
    Access the web interface and navigate to the System > About or Settings > Firmware section to view the current firmware version, or use the device's front panel menu if available
    Affected if The firmware version is less than 8.10 (for example, 8.0x, 7.x, or earlier)
  3. Verify the web interface is enabled
    Check if the device web server is running by accessing the device IP via HTTP/HTTPS, or review the device network configuration for web service status
    Affected if The web interface is accessible and running on the device
  4. Confirm authentication is configured
    Review the web server security settings to verify that user authentication (local or remote) is enabled and that read-only user accounts exist
    Affected if Authentication is enabled and read-only users can access the web interface, allowing them to inject malicious scripts through unsanitized input

If the device is a GE Multilin B30, B90, C60, C70, C95, D30, D60, or F35 relay with firmware version below 8.10 and the web interface is accessible with authenticated users, the environment is affected by CVE-2021-27418.

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.

dbcve · scoped
Upgrade available Upgrade to 8.10 or later
Fixed in 8.10
Interim mitigation

Update GE UR firmware to version 8.1x or later which implements proper input validation and HTML encoding. If updating is not immediately possible, minimize network exposure of the web interface and monitor for suspicious requests.

Recommended fix High confidence

Firmware version 8.10 or later (8.1x series)

  1. Identify the specific Multilin model (B30, B90, C60, C70, C95, D30, D60, or F35) requiring remediation
  2. Download the firmware upgrade package from GE Grid Solutions official website
  3. Review GE upgrade documentation and release notes for version 8.10 or later
  4. Follow GE's standard firmware upgrade procedure for the UR series devices
  5. Verify the upgrade was successful and the web interface properly encodes user input
Caveat Review GE release notes for any configuration or compatibility changes between your current version and 8.10; firmware upgrades on protection relays may require testing to ensure protective functions operate correctly

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Multilin B30 Firmware Scoped from the published advisory
  • Consultation4.0 h
  • Implementation2.0 h
  • Testing4.0 h
  • Review / QA2.0 h
12.0 hours of engineering $2,120
Get the upgrade done

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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-2021-27418 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
  • No spam, self-promotion, credentials, or personal data