Cyber Resilience

CVE-2025-27396

Siemens Scalance Lpe9403 Firmware ≤ 4.0

Published
11 March 2025
Modified
22 August 2025
Patch / advisory
CVSS Score v4 8.7
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0042 35th percentile
Risk Priority 43 floored blend · peak EPSS

Summary

CVE-2025-27396 is a high-severity Improper Check for Dropped Privileges (CWE-273) vulnerability in Siemens Scalance Lpe9403 Firmware. Its CVSS base score is 8.7 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Access Token Manipulation (T1134); ranked at the 35th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-6 (Least Privilege) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2025-27396 affects Siemens SCALANCE LPE9403 devices (part number 6GK5998-3GS00-2AC2) running all firmware versions prior to V4.0. The flaw stems from insufficient privilege checks that allow certain valid operations to be performed without the expected authorization level, corresponding to CWE-273.

An authenticated remote attacker with low privileges can exploit the weakness over the network to escalate rights and obtain full administrative control of the affected device. The CVSS 4.0 score of 8.7 reflects the combination of network reachability, low attack complexity, and high impact on confidentiality, integrity, and availability.

The Siemens advisory SSA-075201 recommends upgrading to firmware version V4.0 or later to correct the privilege enforcement issue and lists no viable workarounds for earlier releases.

EPSS values rose from a low baseline to a recorded peak of 0.0203, indicating emerging exploitation interest after public disclosure.

EU & UK References

Vulnerability Data

A vulnerability has been identified in SCALANCE LPE9403 (6GK5998-3GS00-2AC2) (All versions < V4.0). Affected devices do not properly limit the elevation of privileges required to perform certain valid functionality. This could allow an authenticated lowly-privileged remote attacker to escalate their…

more

privileges.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1134 Access Token Manipulation Stealth
Adversaries may modify access tokens to operate under a different user or system security context to perform actions and bypass access controls.
T1548 Abuse Elevation Control Mechanism Privilege Escalation
Adversaries may circumvent mechanisms designed to control privilege elevation to gain higher-level permissions.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-40574Same product: Siemens Scalance Lpe9403
CVE-2025-40572Same product: Siemens Scalance Lpe9403
CVE-2023-27408Same product: Siemens Scalance Lpe9403
CVE-2025-27393Same product: Siemens Scalance Lpe9403
CVE-2025-40578Same product: Siemens Scalance Lpe9403
CVE-2025-27394Same product: Siemens Scalance Lpe9403
CVE-2023-27409Same product: Siemens Scalance Lpe9403
CVE-2025-40575Same product: Siemens Scalance Lpe9403
CVE-2025-40582Same product: Siemens Scalance Lpe9403
CVE-2025-27392Same product: Siemens Scalance Lpe9403

Affected Assets

siemens
scalance lpe9403 firmware
≤ 4.0

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

Employing least privilege requires that privilege-dropping operations succeed and are verified before continuing.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC activities (code review, static analysis, testing) catch missing or incorrect privilege-drop checks, but eliminating only this one flaw covers only a fraction of the control's broader intent.

PR.AA-05 partial match
prevents

Least-privilege policy and enforcement directly motivate privilege-dropping code, yet the control does not address implementation-level verification of the drop.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing can detect failed privilege drops, yet the control does not require such checks as part of its core intent.

degrades

Control of privileged utility programs includes ensuring privilege-dropping operations are verified before use.

degrades

Privileged access rights policy requires verification that privilege changes succeed, directly addressing failed privilege drops.

prevents

Secure coding practices can prevent missing privilege-drop checks, but the control itself does not mandate verification of privilege changes.

References