RT-Labs P-Net: Denial of service via infinite loop in PDPortDataCheck read
Summary
P-Net, RT-Labs' PROFINET device stack, enters an infinite loop when it handles a read request for the PDPortDataCheck record with subslot 0 (whole module). The port loop never advances, so the device stops responding. A remote, unauthenticated attacker with network access to the device can cause a denial of service that can halt the affected industrial device.
Affected
- RT-Labs P-Net before 1.0.3 (VulDB describes the range as up to 1.0.2)
- Downstream devices and firmware that embed P-Net: unknown, vendor information not found
Fixed in
- P-Net 1.0.3 or later (per CNA record and VulDB; primary advisory RRTL-261019-01 could not be retrieved for verification)
Workaround
Unknown. No mitigation other than upgrading was found in the sources. Check the RT-Labs advisory RRTL-261019-01 for any.
Exploitation
- Known exploited in the wild: no evidence found. CISA KEV: No.
- Public proof of concept: none found; this does not rule one out.
- EPSS: 0.4 % (percentile 34).
Our recommendation
- Inventory PROFINET devices and firmware that embed P-Net and ask the vendors for fixes based on P-Net 1.0.3.
- Confirm these devices are not reachable from the internet or untrusted networks.
- Segment OT networks from IT networks.
- Monitor for devices that stop responding.
- Read the RT-Labs advisory RRTL-261019-01 directly and apply the same 1.0.3 update to the whole advisory batch.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- RT-Labs advisory RRTL-261019-01 rt-labs.com
- VulDB entry 428591 vuldb.com
- Strix CVE-2026-111731 www.strix.ai
- threatint CVE-2026-111731 cve.threatint.com
- VulDB entry 428599 (CVE-2026-112200) vuldb.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 31 Oct 2026, 23:37.
Original description (NVD)
P-Net before 1.0.3 enters an infinite loop when handling a read request for the PDPortDataCheck record with subslot 0 (whole module). The loop over the ports never advanced to the next port, so the request never completes and the device stops responding. A remote unauthenticated attacker can use this to cause a denial of service.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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