Out-of-bounds Write in CODESYS Control
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
The affected products perform improper length checking when parsing incoming HTTP requests, resulting in a size-limited out-of-bounds write. An unauthenticated remote attacker can exploit this flaw to cause a denial of service via a system crash on the affected device.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| CODESYS | CODESYS Control RTE (SL) | 3.5.21.0 to before 3.5.22.20 | 3.5.22.20 | Patch available | CNA |
| CODESYS | CODESYS Control RTE (for Beckhoff CX) SL | 3.5.21.0 to before 3.5.22.20 | 3.5.22.20 | Patch available | CNA |
| CODESYS | CODESYS Control Win (SL) | 3.5.21.0 to before 3.5.22.20 | 3.5.22.20 | Patch available | CNA |
| CODESYS | CODESYS HMI (SL) | 3.5.21.0 to before 3.5.22.20 | 3.5.22.20 | Patch available | CNA |
| CODESYS | CODESYS Runtime Toolkit | 3.5.21.0 to before 3.5.22.20 | 3.5.22.20 | Patch available | CNA |
| CODESYS | CODESYS Control for BeagleBone SL | 4.15.0.0 to before 4.21.0.0 | 4.21.0.0 | Patch available | CNA |
| CODESYS | CODESYS Control for emPC-A/iMX6 SL | 4.15.0.0 to before 4.21.0.0 | 4.21.0.0 | Patch available | CNA |
| CODESYS | CODESYS Control for IOT2000 SL | 4.15.0.0 to before 4.21.0.0 | 4.21.0.0 | Patch available | CNA |
| CODESYS | CODESYS Control for Linux ARM SL | 4.15.0.0 to before 4.21.0.0 | 4.21.0.0 | Patch available | CNA |
| CODESYS | CODESYS Control for Linux SL | 4.15.0.0 to before 4.21.0.0 | 4.21.0.0 | Patch available | CNA |
| CODESYS | CODESYS Control for PFC100 SL | 4.15.0.0 to before 4.21.0.0 | 4.21.0.0 | Patch available | CNA |
| CODESYS | CODESYS Control for PFC200 SL | 4.15.0.0 to before 4.21.0.0 | 4.21.0.0 | Patch available | CNA |
| CODESYS | CODESYS Control for PLCnext SL | 4.15.0.0 to before 4.21.0.0 | 4.21.0.0 | Patch available | CNA |
| CODESYS | CODESYS Control for Raspberry Pi SL | 4.15.0.0 to before 4.21.0.0 | 4.21.0.0 | Patch available | CNA |
| CODESYS | CODESYS Control for WAGO Touch Panels 600 SL | 0.0.0 to before 4.21.0.0 | 4.21.0.0 | Patch available | CNA |
| CODESYS | CODESYS Virtual Control SL | 4.15.0.0 to before 4.21.0.0 | 4.21.0.0 | Patch available | CNA |
- CODESYS Control RTE (SL) VendorCODESYS Affected 3.5.21.0 to before 3.5.22.20 Fixed in 3.5.22.20 Patch available CNA
- CODESYS Control RTE (for Beckhoff CX) SL VendorCODESYS Affected 3.5.21.0 to before 3.5.22.20 Fixed in 3.5.22.20 Patch available CNA
- CODESYS Control Win (SL) VendorCODESYS Affected 3.5.21.0 to before 3.5.22.20 Fixed in 3.5.22.20 Patch available CNA
- CODESYS HMI (SL) VendorCODESYS Affected 3.5.21.0 to before 3.5.22.20 Fixed in 3.5.22.20 Patch available CNA
- CODESYS Runtime Toolkit VendorCODESYS Affected 3.5.21.0 to before 3.5.22.20 Fixed in 3.5.22.20 Patch available CNA
- CODESYS Control for BeagleBone SL VendorCODESYS Affected 4.15.0.0 to before 4.21.0.0 Fixed in 4.21.0.0 Patch available CNA
- CODESYS Control for emPC-A/iMX6 SL VendorCODESYS Affected 4.15.0.0 to before 4.21.0.0 Fixed in 4.21.0.0 Patch available CNA
- CODESYS Control for IOT2000 SL VendorCODESYS Affected 4.15.0.0 to before 4.21.0.0 Fixed in 4.21.0.0 Patch available CNA
- CODESYS Control for Linux ARM SL VendorCODESYS Affected 4.15.0.0 to before 4.21.0.0 Fixed in 4.21.0.0 Patch available CNA
- CODESYS Control for Linux SL VendorCODESYS Affected 4.15.0.0 to before 4.21.0.0 Fixed in 4.21.0.0 Patch available CNA
- CODESYS Control for PFC100 SL VendorCODESYS Affected 4.15.0.0 to before 4.21.0.0 Fixed in 4.21.0.0 Patch available CNA
- CODESYS Control for PFC200 SL VendorCODESYS Affected 4.15.0.0 to before 4.21.0.0 Fixed in 4.21.0.0 Patch available CNA
- CODESYS Control for PLCnext SL VendorCODESYS Affected 4.15.0.0 to before 4.21.0.0 Fixed in 4.21.0.0 Patch available CNA
- CODESYS Control for Raspberry Pi SL VendorCODESYS Affected 4.15.0.0 to before 4.21.0.0 Fixed in 4.21.0.0 Patch available CNA
- CODESYS Control for WAGO Touch Panels 600 SL VendorCODESYS Affected 0.0.0 to before 4.21.0.0 Fixed in 4.21.0.0 Patch available CNA
- CODESYS Virtual Control SL VendorCODESYS Affected 4.15.0.0 to before 4.21.0.0 Fixed in 4.21.0.0 Patch available CNA
Remediation
- Fix · CNA CODESYS Control RTE (SL) (CODESYS) Fixed in 3.5.22.20
- Fix · CNA CODESYS Control RTE (for Beckhoff CX) SL (CODESYS) Fixed in 3.5.22.20
- Fix · CNA CODESYS Control Win (SL) (CODESYS) Fixed in 3.5.22.20
- Fix · CNA CODESYS HMI (SL) (CODESYS) Fixed in 3.5.22.20
- Fix · CNA CODESYS Runtime Toolkit (CODESYS) Fixed in 3.5.22.20
- Fix · CNA CODESYS Control for BeagleBone SL (CODESYS) Fixed in 4.21.0.0
- Fix · CNA CODESYS Control for emPC-A/iMX6 SL (CODESYS) Fixed in 4.21.0.0
- Fix · CNA CODESYS Control for IOT2000 SL (CODESYS) Fixed in 4.21.0.0
- Fix · CNA CODESYS Control for Linux ARM SL (CODESYS) Fixed in 4.21.0.0
- Fix · CNA CODESYS Control for Linux SL (CODESYS) Fixed in 4.21.0.0
- Fix · CNA CODESYS Control for PFC100 SL (CODESYS) Fixed in 4.21.0.0
- Fix · CNA CODESYS Control for PFC200 SL (CODESYS) Fixed in 4.21.0.0
- Fix · CNA CODESYS Control for PLCnext SL (CODESYS) Fixed in 4.21.0.0
- Fix · CNA CODESYS Control for Raspberry Pi SL (CODESYS) Fixed in 4.21.0.0
- Fix · CNA CODESYS Control for WAGO Touch Panels 600 SL (CODESYS) Fixed in 4.21.0.0
- Fix · CNA CODESYS Virtual Control SL (CODESYS) Fixed in 4.21.0.0
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
CODESYS Control RTE (SL), CODESYS Control RTE (for Beckhoff CX) SL and 14 more products 3.5.22.20, 4.21.0.0
2 records Highest priority Priority MEDIUM 1 MEDIUM, 1 LOW
Other records, highest priority first
- TI-2026-07091 Incorrect Authorization in CODESYS ControlPriority LOW 32
Timeline
- 2026-10-02 Threatist record created from CVE-2026-8047
- 2026-10-03 Alias added: GHSA-x9mr-w23g-rxq7
References
More CODESYS vulnerabilities
- TI-2021-12888 CODESYS Control Runtime system before 3.5.17.10 has a Heap-based Buffer Overflow. CVSS 3.1CRITICAL 9.8
- TI-2019-10180 Stack-based buffer overflow in CODESYS V3 web server CVSS 3.1CRITICAL 9.8
- TI-2021-13604 CODESYS V2 web server: crafted requests could trigger a null pointer dereference (DoS) CVSS 3.1HIGH 7.5
- TI-2020-08257 CODESYS V3 web server before 3.5.15.40, as used in CODESYS Control runtime systems, has a buffer overflow. CVSS 3.1CRITICAL 9.8
- TI-2019-13592 CODESYS 3 web server before 3.5.15.20, as distributed with CODESYS Control runtime systems, has a Buffer Overflow. CVSS 3.1CRITICAL 9.8
- TI-2017-03937 Unrestricted file upload in 3S-Smart Software Solutions GmbH CODESYS Web Server CVSS 3.0CRITICAL 9.8
Sources
- CVE-2026-8047 · CVE Program
- CVE-2026-8047 · NVD
- FIRST EPSS
- GHSA-x9mr-w23g-rxq7 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences