VulnerabilityDeferred

CVE-2026-34021

An attacker with access to the communication path between the server and the microcontroller can sniff RS-485 messages and replay previously observed messages.

HIGH 8.6EPSS 0.20%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.20%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 4.0: 8.6 HIGHCVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/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/M
EPSS: 0.20% probability · 9th percentile
CISA KEV: Not listed
Weakness: CWE-294
Source: 551230f0-3615-47bd-b7cc-93e92e730bbf

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.