What’s Vulnerable › Vulnerabilities

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

• Severity: high (CVSS 8.6 v4.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-06-15 · updated 2026-10-25
• Weakness: CWE-294

Description

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.

Affected products

• Wertheim GmbH Wertheim SafeController 5400 Hardware for VAULT ROOMS (Safe Deposit Locker System - Microcontroller): from Wertheim SafeController 5400, Controller 5400 through AssemblyVersion 6.11.8130.22320

References

• https://r.sec-consult.com/wertdev
• https://wertheim-safes.com/safe-deposit-boxes/
• https://sec-consult.com/vulnerability-lab/advisory/multiple-vulnerabilities-in-wertheim-safecontroller-hardware-for-vault-rooms-safe-deposit-locker-system-microcontroller/

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