Siemens SCALANCE Devices Authorization Bypass Through User-Controlled Key (CVE-2025-40805)

critical Tenable OT Security Plugin ID 505079

Synopsis

The remote OT asset is affected by a vulnerability.

Description

Affected devices do not properly enforce user authentication on specific API endpoints. This could facilitate an unauthenticated remote attacker to circumvent authentication and impersonate a legitimate user. Successful exploitation requires that the attacker has learned the identity of a legitimate user.

This plugin only works with Tenable.ot.
Please visit https://www.tenable.com/products/tenable-ot for more information.

Solution

Refer to the vendor advisory.

Plugin Details

Severity: Critical

ID: 505079

File Name: tenable_ot_siemens_CVE-2025-40805.nasl

Version: 1.2

Type: remote

Family: Tenable.ot

Published: 2/10/2026

Updated: 2/11/2026

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: High

Score: 7.3

CVSS v2

Risk Factor: Critical

Base Score: 10

Temporal Score: 7.4

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2025-40805

CVSS v3

Risk Factor: Critical

Base Score: 10

Temporal Score: 8.7

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:siemens:scalance_lpe9433_firmware:2.2, cpe:/o:siemens:scalance_lpe9413_firmware:2.2

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 1/13/2026

Vulnerability Publication Date: 1/13/2026

Reference Information

CVE: CVE-2025-40805

CWE: 639

ICSA: 26-015-08

Detections

Analytics