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TI-2026-80289 Aliases CVE-2026-82946GHSA-m2qv-7w8c-3r6g

NULL pointer dereference in SOEM mailbox error handling

Priority LOW 28CWE-476Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-476.

Summary

SOEM from RT-Labs AB, version 2.0.0 and earlier, contains a NULL pointer dereference (CWE-476) in its mailbox error handling. When the software receives an error response, it clears an internal pointer but keeps processing, so a second message that arrives before timeout makes it use the cleared pointer and crash. A malicious device on the network can crash the master system with a simple sequence of two messages, without authentication.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

SOEM version 2.0.0 and earlier contains a vulnerability where a malicious device can crash the master system. When the software receives an error response, it clears an internal pointer but continues processing. If another message arrives before timeout, the software attempts to use the cleared pointer, causing a crash. An attacker can trigger this with a simple sequence of two messages.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00169 6th percentileScored 2026-11-07
Fix Fixed SOEM (RT-Labs AB): 2.0.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
RT-LabsSOEMbefore 2.0.12.0.1Patch availableCNA
  • SOEM VendorRT-Labs Affected before 2.0.1 Fixed in 2.0.1 Patch available CNA

Remediation

Update SOEM from RT-Labs AB to version 2.0.1, which fixes the flaw. The sources list no advisory identifier for this fix.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA SOEM (RT-Labs AB) Fixed in 2.0.1

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Advisory ·

    RT-Labs SOEM — rt-labs.com/wp-content/uploads/2026/10/RRTL-260921-01.pdf

    6 records Highest priority Priority LOW 6 LOW

    Other records, highest priority first

    • TI-2026-80287 Buffer overflow in SOEM CoE SDO multi-segment data transfersPriority LOW 39
    • TI-2026-80282 SOEM Memory Corruption via Integer Underflow in Message Length ValidationPriority LOW 37
    • TI-2026-80300 Out-of-bounds reads in SOEM frame processing expose memoryPriority LOW 30
    Show all 6 records → Advisory →

Timeline

  1. 2026-10-26 Threatist record created from CVE-2026-82946
  2. 2026-10-26 CISA SSVC decision points changed
  3. 2026-10-26 Priority changed: MEDIUM → LOW
  4. 2026-10-27 Alias added: GHSA-m2qv-7w8c-3r6g

References

Advisory 1

  • TI-2026-82626 Out-of-bounds write when parsing AR Vendor Block requests in RT-Labs P-Net CVSS 4.0CRITICAL 9.3
  • TI-2026-82632 Resource exhaustion from RPC sessions kept for unknown interface requests CVSS 4.0HIGH 8.7
  • TI-2026-82630 NULL pointer dereference in RT-Labs P-Net on implicit read requests CVSS 4.0HIGH 8.7
  • TI-2026-82627 NULL pointer dereference in P-Net lets remote attackers crash devices CVSS 4.0HIGH 8.7
  • TI-2026-82625 Infinite loop in RT-Labs P-Net PDPortDataCheck record handling CVSS 4.0HIGH 8.7
  • TI-2025-23482 Out-of-bounds write in RT-Labs P-Net CVSS 3.1CRITICAL 9.8
See all 28 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences