Rockwell Automation Flex 5000 Adapter
All CISA Advisories, CISA, July 16, 2026
Summary
Successful exploitation of this vulnerability could allow an attacker to cause a denial-of-service condition on the affected product.
The following versions of Rockwell Automation Flex 5000 Adapter are affected:
- Flex 5000 Adapter 6.011 (CVE-2026-12659)
| CVSS | Vendor | Equipment | Vulnerabilities |
|---|---|---|---|
| v3 7.5 | Rockwell Automation | Rockwell Automation Flex 5000 Adapter | Double Free |
Background
- Critical Infrastructure Sectors: Critical Manufacturing, Information Technology
- Countries/Areas Deployed: Worldwide
- Company Headquarters Location: United States
Vulnerabilities
CVE-2026-12659
A denial-of-service security issue exists in the affected products. The security issue stems from improper handling of exceptional conditions when processing crafted CIP packets sent to the adapter. A power cycle is required to recover the module and associated I/O.
Affected Products
Rockwell Automation Flex 5000 Adapter
Rockwell Automation
Rockwell Automation Flex 5000 Adapter: 6.011
known_affected
Remediations
Vendor fix
Rockwell Automation recommends users to upgrade to the following: Flex 5000 Adapter version 6.012.
Mitigation
Customers using the affected software, who are not able to upgrade to one of the corrected versions, should use Rockwell Automation’s security best practices (https://support.rockwellautomation.com/app/answers/answer_view/a_id/1085012/loc/en_US#__highlight).
https://support.rockwellautomation.com/app/answers/answer_view/a_id/1085012/loc/en_US#__highlight
Mitigation
For more information, see Rockwell Automation Security Advisory SD1789 (https://www.rockwellautomation.com/en-us/trust-center/security-advisories/advisory.SD1789.html).
https://www.rockwellautomation.com/en-us/trust-center/security-advisories/advisory.SD1789.html
Relevant CWE: CWE-415 Double Free
Metrics
| CVSS Version | Base Score | Base Severity | Vector String |
|---|---|---|---|
| 3.1 | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 4.0 | 8.7 | HIGH | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
Acknowledgments
- Rockwell Automation reported this vulnerability to CISA
Legal Notice and Terms of Use
This product is provided subject to this Notification (https://www.cisa.gov/notification) and this Privacy & Use policy (https://www.cisa.gov/privacy-policy).
Recommended Practices
CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability.
Minimize network exposure for all control system devices and/or systems, ensuring they are not accessible from the internet.
Locate control system networks and remote devices behind firewalls and isolating them from business networks.
When remote access is required, use more secure methods, such as Virtual Private Networks (VPNs), recognizing VPNs may have vulnerabilities and should be updated to the most current version available. Also recognize VPN is only as secure as the connected devices.
CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.
CISA also provides a section for control systems security recommended practices on the ICS webpage on cisa.gov/ics. Several CISA products detailing cyber defense best practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies.
CISA encourages organizations to implement recommended cybersecurity strategies for proactive defense of ICS assets.
Additional mitigation guidance and recommended practices are publicly available on the ICS webpage at cisa.gov/ics in the technical information paper, ICS-TIP-12-146-01B–Targeted Cyber Intrusion Detection and Mitigation Strategies.
Organizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents.
CISA also recommends users take the following measures to protect themselves from social engineering attacks:
Do not click web links or open attachments in unsolicited email messages.
Refer to Recognizing and Avoiding Email Scams for more information on avoiding email scams.
Refer to Avoiding Social Engineering and Phishing Attacks for more information on social engineering attacks.
No known public exploitation specifically targeting this vulnerability has been reported to CISA at this time.
Revision History
- Initial Release Date: 2026-07-16
| Date | Revision | Summary |
|---|---|---|
| 2026-07-16 | 1 | Initial Republication of Rockwell Automation Security Advisory SD1789 |
