Description
The RCU II+ and Multiload II+ are vulnerable to an unauthenticated service that exposes a debug interface granting full root-level access to the embedded system. This vulnerability stems from a network-accessible port running a Target Communications Framework (TCF) service that does not require any authentication, allowing an attacker to directly interact with the Linux environment that powers the device. Once connected, an attacker can freely view and modify the filesystem, manipulate running processes, and control network interfaces, enabling deep alteration of system behavior.
References6
- github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/i…
- s3.amazonaws.com/docs.toptech.com/index.html#downloads/Firmware…
- s3.amazonaws.com/docs.toptech.com/nonpublic/2025%2012%2001%20RC…
- s3.amazonaws.com/docs.toptech.com/nonpublic/rcuiip_mliip_vrt.gz
- s3.amazonaws.com/docs.toptech.com/nonpublic/rcuiip_mliip_vrt.zip
- www.cisa.gov/news-events/ics-advisories/icsa-26-211-03
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: CNA
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 4.0
-
8.7
HIGH
Score source: CNA
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/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 — exploit probability
- 0% percentile: 40 · as of 13 November 2026
- CWE
- CWE-306
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.