<span>Horner Automation Cscape and XL4, XL7 PLC</span> <span><span>apeterson</span></span> <span><time datetime="2026-04-16T12:16:32-04:00" title="Thursday, April 16, 2026">Apr 16, 2026</time> </span> <div class="c-field c-field--name-field-release-date c-field--type-datetime c-field--label-above"> <div class="c-field__label">Release Date</div><div class="c-field__content"><time datetime="2026-04-16T12:00:00Z">April 16, 2026</time></div></div> <div class="c-field c-field--name-field-description c-field--type-text-long c-field--label-above"> <div class="c-field__label">Description</div><div class="c-field__content"><p><a href="https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-106-02.json"><strong>View CSAF</strong></a></p><h2>Summary</h2><p><strong>Successful exploitation of this vulnerability could allow an attacker to gain unauthorized access to systems and services.</strong></p><p>The following versions of Horner Automation Cscape and XL4, XL7 PLC are affected:</p><ul><li>Cscape v10.0</li><li>XL7 PLC v15.60</li><li>XL4 PLC v16.32.0</li></ul><div class="csaf-table"><table class="tablesaw tablesaw-stack" data-tablesaw-mode="stack" data-tablesaw-minimap><thead><tr><th role="columnheader" data-tablesaw-priority="persist">CVSS</th><th role="columnheader">Vendor</th><th role="columnheader">Equipment</th><th role="columnheader">Vulnerabilities</th></tr></thead><tbody><tr><td>v3 9.1</td><td>Horner Automation</td><td>Horner Automation Cscape and XL4, XL7 PLC</td><td>Weak Password Requirements</td></tr></tbody></table></div><h3>Background</h3><ul><li><strong>Critical Infrastructure Sectors: </strong>Critical Manufacturing</li><li><strong>Countries/Areas Deployed: </strong>Worldwide</li><li><strong>Company Headquarters Location: </strong>United States</li></ul><hr><h2>Vulnerabilities</h2><div class="csaf-accordion"><p><a class="csaf-accordion-toggle-all" href="#">Expand All +</a></p><div class="csaf-accordion-item"><h3><a class="csaf-accordion-toggle" href="#">CVE-2026-6284</a></h3><div class="csaf-accordion-content"><p>An attacker with network access to the PLC is able to brute force discover passwords to gain unauthorized access to systems and services. The limited password complexity and no password input limiters makes brute force password enumeration possible.</p><p><a href="https://www.cve.org/CVERecord?id=CVE-2026-6284">View CVE Details</a></p><hr><h4>Affected Products</h4><h5>Horner Automation Cscape and XL4, XL7 PLC</h5><div class="ics-vendor-version-status"><div class="ics-vendor"><strong>Vendor:</strong><br>Horner Automation</div><div class="ics-version"><strong>Product Version:</strong><br>Horner Automation Cscape: v10.0, Horner Automation XL7 PLC: v15.60, Horner Automation XL4 PLC: v16.32.0</div><div class="ics-status"><strong>Product Status:</strong><br>known_affected</div></div><div class="ics-remediations"><h6>Remediations</h6><p><strong>Vendor fix</strong><br>Horner Automation recommends users update to Cscape v10.2 SP2 or later. Horner Automation has also released the latest firmware for both XL4 and XL7 PLCs. Horner recommends users update to the latest version of the firmware. https://hornerautomation.com/cscape-software-free/cscape-software/.<br><a href="https://hornerautomation.com/cscape-software-free/cscape-software/">https://hornerautomation.com/cscape-software-free/cscape-software/</a></p><p><strong>Mitigation</strong><br>For more information, see Horner Automation's release notes.</p></div><p><strong>Relevant CWE:</strong><a href="https://cwe.mitre.org/data/definitions/521.html">CWE-521 Weak Password Requirements</a></p><hr><h4>Metrics</h4><div class="csaf-table csaf-metrics-table"><table class="tablesaw tablesaw-stack" data-tablesaw-mode="stack" data-tablesaw-minimap><thead><tr><th role="columnheader" data-tablesaw-priority="persist">CVSS Version</th><th role="columnheader">Base Score</th><th role="columnheader">Base Severity</th><th role="columnheader">Vector String</th></tr></thead><tbody><tr><td>3.1</td><td>9.1</td><td>CRITICAL</td><td><a href="https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N">CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N</a></td></tr></tbody></table></div></div></div></div><hr><h2>Acknowledgments</h2><ul><li>An anonymous researcher reported this vulnerability to CISA</li></ul><hr><h2>Legal Notice and Terms of Use</h2><p>This product is provided subject to this Notification (https://www.cisa.gov/notification) and this Privacy &amp; Use policy (https://www.cisa.gov/privacy-policy).</p><hr><h2>Recommended Practices</h2><p>CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability.</p><p>Minimize network exposure for all control system devices and/or systems, ensuring they are not accessible from the internet.</p><p>Locate control system networks and remote devices behind firewalls and isolating them from business networks.</p><p>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.</p><p>CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.</p><p>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.</p><p>CISA encourages organizations to implement recommended cybersecurity strategies for proactive defense of ICS assets.</p><p>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.</p><p>Organizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents.</p><p>No known public exploitation specifically targeting this vulnerability has been reported to CISA at this time.</p><hr><h2>Revision History</h2><ul><li><strong>Initial Release Date: </strong>2026-04-16</li></ul><table class="tablesaw tablesaw-stack" data-tablesaw-mode="stack" data-tablesaw-minimap><thead><tr><th role="columnheader" data-tablesaw-priority="persist">Date</th><th role="columnheader">Revision</th><th role="columnheader">Summary</th></tr></thead><tbody><tr><td>2026-04-16</td><td>1</td><td>Initial Publication</td></tr></tbody></table><hr><h2>Legal Notice and Terms of Use</h2></div></div> <div class="c-field c-field--name-field-advisory-type c-field--type-entity-reference c-field--label-above"> <div class="c-field__label">Advisory Type</div><div class="c-field__content">ICS Advisory</div></div> <div class="c-field c-field--name-field-topics c-field--type-entity-reference c-field--label-inline"> <div class="c-field__label is-inline">Topics</div><div class="c-field__content"><a href="https://www.cisa.gov/topics/industrial-control-systems/industrial-control-system-vulnerabilities">Industrial Control System Vulnerabilities</a>, <a href="https://www.cisa.gov/topics/industrial-control-systems">Industrial Control Systems</a></div></div> <div class="c-field c-field--name-field-alert-code c-field--type-string c-field--label-above"> <div class="c-field__label">Alert Code</div><div class="c-field__content">ICSA-26-106-02</div></div> <div class="c-field c-field--name-field-sector c-field--type-entity-reference c-field--label-inline"> <div class="c-field__label is-inline">Sector</div><div class="c-field__content"><a href="https://www.cisa.gov/topics/critical-infrastructure-security-and-resilience/critical-infrastructure-sectors/critical-manufacturing-sector" hreflang="en">Critical Manufacturing Sector</a></div></div> <div class="c-field c-field--name-field-vendor c-field--type-entity-reference c-field--label-above"> <div class="c-field__label">Vendor</div><div class="c-field__content">Horner Automation</div></div> <div class="c-field c-field--name-field-key-takeaways-toggle c-field--type-boolean c-field--label-above"> <div class="c-field__label">Show 'Key Takeaways' block</div><div class="c-field__content">Off</div></div> <div class="c-field c-field--name-field-imported c-field--type-boolean c-field--label-hidden"> <div class="c-field__content">On</div></div>