# CVE-2026-9625: Rockwell Automation RSLinx Classic denial-of-service in CIP packet handling

Source: https://junglewise.ai/threats/cve-2026-9625-rockwell-automation-rslinx-classic-denial-of-service-in-cip-packet  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-01. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-9625 · Severity: info · CVSS 8.7 · Published 2026-09-01

RSLinx Classic is industrial automation software from Rockwell Automation that connects Allen-Bradley devices and applications, running as a Windows service to manage real-time data access and control. An attacker can send a specially crafted network packet (CIP protocol) with an oversized embedded message to crash the service, forcing a restart and causing an operational outage in industrial automation environments.

Technologies: [Rockwell Automation RSLinx Classic](https://junglewise.ai/threats/technologies/rslinx-classic). Vendors: [Rockwell Automation](https://junglewise.ai/threats/vendors/rockwell-automation).

## Quick answers

**Is CVE-2026-9625 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-9625 being exploited in the wild.

**How severe is CVE-2026-9625?** Informational severity, with a CVSS score of 8.7, published 1 September 2026.

**Which products and versions are affected?** Rockwell Automation RSLinx Classic 4.50 and prior.

**Is there a fix for CVE-2026-9625?** A patch was published on 2026-09-01: Patch available in RSLinx Classic v4.60 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-9625 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-9625?** Check whether you run Rockwell Automation RSLinx Classic at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

CVE-2026-9625 is a buffer overflow vulnerability (CWE-120) in RSLinx Classic's CIP packet handling. The vulnerability occurs when processing a crafted CIP packet containing an oversized embedded message request, causing insufficient bounds checking on the input data. The attack is network-based and requires no authentication or user interaction—an attacker only needs network connectivity to the service to send the malicious packet. Successful exploitation results in a crash of the RSLinx Classic service, requiring manual restart. The vulnerability affects versions 4.50 and prior; patches are available in version 4.60 and later.

## Affected products

- Rockwell Automation RSLinx Classic 4.50 and prior

## Timeline

- 2026-09-01: disclosed
- 2026-09-01: patched: Patch available in RSLinx Classic v4.60

## References

- [https://www.rockwellautomation.com/en-us/trust-center/security-advisories/advisory.SD1794.html](https://www.rockwellautomation.com/en-us/trust-center/security-advisories/advisory.SD1794.html)

## Related threats

- [Rockwell Automation RSLinx Classic denial-of-service via malformed CIP packet](https://junglewise.ai/threats/cve-2026-9624-rockwell-automation-rslinx-classic-denial-of-service-via-malformed)
- [Rockwell Automation RSLinx Classic denial-of-service in Forward Close service](https://junglewise.ai/threats/cve-2026-9622-rockwell-automation-rslinx-classic-denial-of-service-in-forward)
- [Rockwell Automation RSLinx Classic denial-of-service via malformed CIP packet](https://junglewise.ai/threats/cve-2026-9621-rockwell-automation-rslinx-classic-denial-of-service-via-malformed)