Incorrect Privilege AssignmentWeakness · CWE-266

CVE-2026-9397

HIGH · 8.1 CVSS v3.1 Published 2026-05-24
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
90/100
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
A weakness has been identified in Besen BS20 EV Charging Station up to 20260426. Affected by this issue is some unknown functionality of the component OTA Update Installation Handler. This manipulation causes improper authorization. The attack is possible to be carried out remotely. A high degree of complexity is needed for the attack. The exploitation is known to be difficult. The original disclosure mentions, that "[t]hese vulnerabilities have been reported to Besen and we have received their acknowlegement that they are reviewing this as of April 2026."

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 Besen BS20 EV Charging Station contains an improper authorization vulnerability in its OTA (Over-The-Air) Update Installation Handler. This allows a remote attacker to potentially install unauthorized firmware updates without proper authentication or authorization checks. The vulnerability affects the firmware update mechanism up to the April 2026 version.

MitigationApply vendor-supplied firmware patches when available. Until then, isolate the charging station network segment, disable OTA update functionality if possible, and monitor for unauthorized update attempts.

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
Network
Complexity
High
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:H/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. Confirm device model
    Identify the Besen BS20 EV Charging Station in your environment by checking the device label, management interface, or network inventory. Compare the model number to the affected product name.
    Affected if The device is a Besen BS20 EV Charging Station and OTA updates are enabled
  2. Locate OTA update configuration
    Access the device management interface or configuration panel and navigate to the OTA (Over-the-Air) Update settings. Look for options related to firmware updates, remote updates, or update installation.
    Affected if OTA update functionality is enabled or configured on the device
  3. Verify OTA endpoint exposure
    Check network configuration to determine if the OTA update endpoint is accessible from network segments outside of authorized management networks. Review firewall rules, ACLs, or network policies applied to the device.
    Affected if OTA update endpoints are reachable from untrusted or unauthorized network segments
  4. Inspect OTA authorization controls
    Review the OTA update handler configuration for any authentication requirements, authorization checks, or access control settings. Look for settings that control who can initiate or approve firmware updates.
    Affected if No strong authentication or authorization is required to trigger or install OTA updates
  5. Review update installation logs
    Examine device logs, system logs, or management platform logs for any OTA update attempts, particularly those from unexpected sources, at unusual times, or lacking proper authorization markers.
    Affected if Unauthorized or unexpected OTA update attempts are logged or detectable

You are affected if you have a Besen BS20 EV Charging Station with OTA update functionality enabled and the OTA update endpoints are accessible without proper authorization controls.

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

Apply vendor-supplied firmware patches when available. Until then, isolate the charging station network segment, disable OTA update functionality if possible, and monitor for unauthorized update attempts.

Have this fixed Scoped from the published advisory
  • Consultation8.0 h
  • Implementation16.0 h
  • Testing12.0 h
  • Review / QA8.0 h
44.0 hours of engineering $7,720
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $12,352.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-9397 — 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-2026-9397 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