Vulnerability · Published Sep 30, 2026 · Assigned by CERTVDE
CVE-2026-76992Uncontrolled Memory Allocation in CODESYS Gateway Client
High 7.5
In plain English
A high-severity resource allocation without limits in Development System 3 from CODESYS. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 26% of all known vulnerabilities).
Official description
The CODESYS Gateway Client allocates memory based on a size field in a gateway response without enforcing an appropriate upper limit. An unauthenticated remote attacker controlling a malicious gateway can exploit this behavior to trigger excessive memory consumption, resulting in a denial-of-service condition thus leading to a total loss of availablity.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| CODESYS | Development System 3 | 3.0.0.0 – before 3.5.22.40 |
| CODESYS | Gateway | 3.0.0.0 – before 3.5.22.40 |
| CODESYS | Edge Gateway for Windows | 3.0.0.0 – before 3.5.22.40 |
| CODESYS | HMI (SL) | 3.0.0.0 – before 3.5.22.40 |
| CODESYS | OPC DA Server SL | 3.0.0.0 – before 3.5.22.40 |
| CODESYS | PLCHandler | 3.0.0.0 – before 3.5.22.40 |
| CODESYS | Runtime Toolkit | 3.0.0.0 – before 3.5.22.40 |
| CODESYS | Edge Gateway for Linux | 3.15.0.0 – before 4.23.0.0 |
Weakness: CWE-770 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H