CVE-2020-5802 Denial of service in Rockwell FactoryTalk Linx

What is CVE-2020-5802?

CVE-2020-5802 is a high-severity denial of service vulnerability in Rockwell FactoryTalk Linx, published on 29 Dec 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

An attacker-controlled memory allocation size can be passed to the C++ new operator in RnaDaSvr.dll by sending a specially crafted ConfigureItems message to TCP port 4241. This will cause an unhandled exception, resulting in termination of RSLinxNG.exe. Observed in FactoryTalk 6.11. All versions of FactoryTalk Linx are affected.

Weakness: CWE-770

Which versions are affected by CVE-2020-5802?

It affects 1 product.

Products include Rockwellautomation Factorytalk Linx.

How do I fix CVE-2020-5802?

No fix has been published for CVE-2020-5802 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2020-5802 being exploited?

There is no known exploitation of CVE-2020-5802 in the wild and no public exploit code.

Other vulnerabilities in Rockwell FactoryTalk Linx

• CVE-2020-27251 Memory corruption in FactoryTalk Linx Critical 9.8
• CVE-2020-12001 Path traversal in FactoryTalk Linx, RSLinx Classic, Connected Components Workbench, ControlFLASH Plus, FactoryTalk Asset Centre, FactoryTalk Linx CommDTM, Studio 5000 Launcher, Studio 5000 Logix Designer software Critical 9.8
• CVE-2025-9067 Rockwell Automation FactoryTalk® Linx Privilege Escalation Vulnerabilities High 8.5
• CVE-2025-9068 Rockwell Automation FactoryTalk® Linx Privilege Escalation Vulnerabilities High 8.5
• CVE-2025-7972 Rockwell Automation FactoryTalk® Linx Network Browser Security Bypass Vulnerability High 8.4

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-43mv-m2vr-rqqc.