CVE-2026-12562 json
Toptech Systems RCU II+ and Multiload II+ Missing Authentication for Critical Function
published 2026-07-30 3 mo ago modified 2026-09-08 2 mo ago also EUVD-2026-51329
- cvss
- 8.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 39%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- Toptech Systems RCU II+ 2025-11-24
- Toptech Systems Multiload II+ 2025-11-24
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
cisa ICSA-26-211-03 updated cvss 8.8
Toptech Systems RCU II+ and Multiload II+
-
Toptech Systems Multiload II+ <2025-11-24 Toptech Systems RCU II+ <2025-11-24affected: mitigation “Toptech Systems provides two methods for remediating affected RCU II+ and Multiload II+ units: First, move the device to a closed or segmented network without untrusted access.” s3.amazonaws.com
From CISA ICS and IT advisories (CSAF, https://github.com/cisagov/CSAF), a U.S. Government work; changed: reduced to products, statuses and remediations. CISA notification · csaf
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 3 mo ago
Exploit prediction
0.46% chance of exploitation in the next 30 days, higher than 39% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.8 | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| CNA | 4.0 | 8.7 | 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 |
| CNA | 4.0 | 8.7 | 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 |
Affected products
- Toptech Systems RCU II+
- Toptech Systems Multiload II+
Classification
- Weakness
-
- CWE-306 Missing Authentication for Critical Functionality
References
- s3.amazonaws.com /docs.toptech.com/nonpublic/rcuiip_mliip_vrt.zip
- s3.amazonaws.com /docs.toptech.com/nonpublic/rcuiip_mliip_vrt.gz
- s3.amazonaws.com /docs.toptech.com/index.html#downloads/Firmware/RCUII+_MLII+_SMPII+/
- s3.amazonaws.com /docs.toptech.com/nonpublic/2025%2012%2001%20RCU%20IIPlus%20MultiLoad%20IIPlus%20Vulnerability%20Notice.pdf
- cisa.gov /news-events/ics-advisories/icsa-26-211-03
- github.com /cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-211-03.json
Sources
- CVE List CVE-2026-12562
- NVD CVE-2026-12562
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