Quick answers
- Is CVE-2026-9637 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-9637 being exploited in the wild.
- How severe is CVE-2026-9637?
- Informational severity, with a CVSS score of 8.7, published 1 September 2026.
- Which products and versions are affected?
- Rockwell Automation CompactGuardLogix 5380 V33 and prior, V34.011–V34.014, V35.011–V35.013, V36.011–V36.012; Rockwell Automation CompactLogix 5380 V33 and prior, V34.011–V34.014, V35.011–V35.013, V36.011–V36.012; Rockwell Automation ControlLogix 5580 V33 and prior, V34.011–V34.014, V35.011–V35.013, V36.011–V36.012; Rockwell Automation GuardLogix 5580 V33 and prior, V34.011–V34.014, V35.011–V35.013, V36.011–V36.012.
- Is there a fix for CVE-2026-9637?
- A patch was published on 2026-09-01: Corrected firmware versions available: V37.011, V36.013, V35.014, V34.015 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-9637 attacked?
- It is attacked over the network, in a network appliance.
- Am I affected by CVE-2026-9637?
- Check whether you run Rockwell Automation CompactGuardLogix 5380, Rockwell Automation CompactLogix 5380, Rockwell Automation ControlLogix 5580 or one of the others listed 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
The vulnerability is a buffer overflow (CWE-119) in CIP message processing on Logix platforms. The root cause is improper validation of input length during message parsing, allowing an attacker to trigger a major nonrecoverable fault (MNRF) that crashes the controller. The attack is network-accessible and requires no authentication or user interaction. An attacker can repeatedly send malformed CIP messages to cause denial of service; remediation requires upgrading to corrected firmware versions (V37.011, V36.013, V35.014, or V34.015) for each affected product line.
Affected products
- Rockwell Automation ControlLogix 5580 V33 and prior, V34.011–V34.014, V35.011–V35.013, V36.011–V36.012
- Rockwell Automation CompactLogix 5380 V33 and prior, V34.011–V34.014, V35.011–V35.013, V36.011–V36.012
- Rockwell Automation GuardLogix 5580 V33 and prior, V34.011–V34.014, V35.011–V35.013, V36.011–V36.012
- Rockwell Automation CompactGuardLogix 5380 V33 and prior, V34.011–V34.014, V35.011–V35.013, V36.011–V36.012
Timeline
- 2026-09-01: disclosed: Security advisory SD1792 published by Rockwell Automation
- 2026-09-01: patched: Corrected firmware versions available: V37.011, V36.013, V35.014, V34.015
- 2026-09-01: kev added: Listed as Known Exploited Vulnerability (KEV)