Missing AuthenticationWeakness · CWE-306

CVE-2025-27256

HIGH · 8.3 CVSS v3.1 Published 2025-03-10
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
88/100
Remediation priority · High
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
Missing Authentication for Critical Function vulnerability in GE Vernova Enervista UR Setup application allows Authentication Bypass due to a missing SSH server authentication. Since the client connection is not authenticated, an attacker may perform a man-in-the-middle attack on the network.

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

The GE Vernova Enervista UR Setup application contains a missing authentication vulnerability in its SSH server implementation. The application fails to authenticate the SSH server during client connections, allowing an unauthenticated attacker to intercept communications through a man-in-the-middle attack. This authentication bypass affects the critical SSH communication channel used for device configuration and management.

MitigationImplement proper SSH server authentication using validated host keys or certificates to prevent man-in-the-middle attacks. Ensure SSH connections verify the server identity before establishing encrypted sessions, and consider network segmentation to limit exposure of the Enervista UR Setup service.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

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
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
High
Availability
High

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/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 if Enervista UR Setup is installed
    Check for the presence of the GE Vernova Enervista UR Setup application in the system (typically found in Program Files or installation directories on Windows systems where the software is deployed)
    Affected if The application is installed and the SSH server component is in use
  2. Locate the SSH server configuration
    Search for SSH server configuration files or settings within the Enervista UR Setup installation directory, looking for SSH daemon or server-related config files
    Affected if SSH server configuration exists and is enabled
  3. Check for host keys or certificates
    Examine the SSH server configuration for the presence and proper configuration of host keys (such as ssh_host_rsa_key, ssh_host_ecdsa_key) or certificate files
    Affected if No host keys or certificates are defined or they are missing from the SSH server configuration
  4. Verify SSH client verification settings
    Review SSH client configuration or connection settings to determine whether server identity verification (host key verification) is enabled or enforced
    Affected if Clients are configured to connect without verifying the server's identity or host key
  5. Test SSH connection for MITM vulnerability
    Attempt an SSH connection from a client to the Enervista UR Setup SSH server and inspect whether the server presents a valid host key that the client can verify
    Affected if The SSH server does not present a verifiable host key or the client accepts connections without host key verification

The environment is affected if the Enervista UR Setup application is installed with its SSH server component enabled and the server fails to present authenticated host keys or certificates to connecting clients, allowing MITM attacks.

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 proper SSH server authentication using validated host keys or certificates to prevent man-in-the-middle attacks. Ensure SSH connections verify the server identity before establishing encrypted sessions, and consider network segmentation to limit exposure of the Enervista UR Setup service.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA2.0 h
20.0 hours of engineering $3,500
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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-2025-27256 in production — separate from our analysis above.

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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
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  • Version or environment caveats, and links to real fixes
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