CVE-2026-34021 HIGH

CVE-2026-34021: Lack of cryptographic protection in Wertheim SafeController 5400 enables RS-485 message sniffing and replay

Vendor Wertheim Gmbh
Product Wertheim SafeController 5400 Hardware for VAULT ROOMS (Safe Deposit Locker System - Microcontroller)
Weakness CWE-294
Published June 15, 2026
Last update June 15, 2026
View on NVD All CVEs

CVSS base score

8.6/10
Attack vector Adjacent
Attack complexity Low
Privileges required None
User interaction None
Confidentiality —
Integrity —

CVSS vector

CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

What the vulnerability does

01Description

The Wertheim SafeController 5400, Controller 5400 - AssemblyVersion 6.11.8130.22320, uses RS-485 communication between the server and the microcontroller without cryptographic protection. An attacker with access to the communication path between the server and the microcontroller can sniff RS-485 messages and replay previously observed messages. This can be used, for example, to spoof a "quit alarm" message and continuously deactivate the safe alarm.

Key dates

02Disclosure timeline

June 15, 2026 CVE published
June 15, 2026 Record updated