CVE-2026-9624: CWE-191 Integer underflow (wrap or wraparound) in Rockwell Automation RSLinx Classic®
Description
A denial-of-service security issue exists within RSLinx® Classic. A crafted CIP packet can cause the RSLinx® Classic service to crash due to insufficient data length validation, requiring a restart of the service to recover.
CVSS v4.0
Score 8.7high
Affected software
Rockwell Automation
RSLinx Classic®
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves an integer underflow condition in RSLinx Classic due to improper validation of CIP packet data length. A specially crafted packet can trigger this flaw, causing the service to crash and become unavailable until restarted. The issue is classified under CWE-191 and results in a denial-of-service condition. The CVSS 4.0 base score is 8.7, indicating high severity, with network attack vector, no privileges or user interaction required, and high impact on availability. No vendor remediation or patch information is currently available.
Potential Impact
Successful exploitation causes a denial-of-service by crashing the RSLinx Classic service, disrupting its operation until a manual restart is performed. There is no indication of data compromise or privilege escalation. The impact is limited to service availability.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, monitoring for unusual CIP packet traffic and preparing for manual service restarts may be necessary.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Rockwell
- Date Reserved
- 2026-05-26T17:18:42.313Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6a96d8b2acd9273b49c6bfa4
Added to database: 09/01/2026, 13:52:50 UTC
Last enriched: 09/07/2026, 14:43:37 UTC
Last updated: 10/15/2026, 18:48:26 UTC
Views: 69
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