CVE-2026-9621: CWE-190 Integer overflow or wraparound in Rockwell Automation RSLinx Classic®
Description
A denial-of-service security issue exists within RSLinx® Classic. The security issue stems from improper handling of a malformed packet. A crafted CIP packet can cause the RSLinx® Classic service to crash, requiring a restart of the service to recover
CVSS v4.0
Score 9.2critical
Affected software
Rockwell Automation
RSLinx Classic®
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability in RSLinx Classic involves an integer overflow or wraparound condition triggered by a crafted CIP packet. When such a malformed packet is processed, it causes the RSLinx Classic service to crash, resulting in a denial-of-service condition. The CVSS 4.0 base score is 9.2, indicating a critical severity with network attack vector, no privileges or user interaction required, and high impact on availability. No vendor advisory or patch information is currently available.
Potential Impact
Successful exploitation causes the RSLinx Classic service to crash, leading to denial of service and requiring manual service restart. There is no indication of code execution or data compromise from the provided data.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, monitor for malformed CIP packets and consider network-level protections to limit exposure to untrusted sources.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Rockwell
- Date Reserved
- 2026-05-26T17:18:12.101Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6a96d527acd9273b49c2e067
Added to database: 09/01/2026, 13:37:43 UTC
Last enriched: 09/07/2026, 14:43:22 UTC
Last updated: 10/14/2026, 18:48:26 UTC
Views: 67
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