BS20 EV Charging Station: Incorrect Privilege Assignment
CVE-2026-9397 is a high-severity incorrect privilege assignment vulnerability in BS20 EV Charging Station from Besen, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected BS20 EV Charging Station versions: 20260426. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.45% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of BS20 EV Charging Station you run against the affected versions below, and install the vendor's latest release.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Besen | BS20 EV Charging Station | 20260426 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- HighSuccess depends on conditions outside the attacker's control.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (vuldb.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.2 | High | CNA (vuldb.com) |
| CVSS 3.1 | 8.1 | High | CNA (vuldb.com) |
| CVSS 2.0 | 7.6 | High | CNA (vuldb.com) |
Official description
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."
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Incorrect Privilege Assignment
A product incorrectly assigns a privilege to a particular actor, creating an unintended sphere of control for that actor.
How developers prevent this class of flaw
- Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.
- Run your code using the lowest privileges that are required to accomplish the necessary tasks. If possible, create isolated accounts with limited privileges that are only used for a single task. That way, a successful attack will not immediately give the attacker access to the rest of the software or its environment. For example, database applications rarely need to run as the database administrator, especially in day-to-day operations.
More Incorrect Privilege Assignment vulnerabilities (CWE-266)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other references
Recent Incorrect Privilege Assignment vulnerabilities
- 7.8 High severity
- 9.8 Critical severity
- 7.5 High severity
- 7.8 High severity
- 8.1 High severity
- 9.9 Critical severity
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