Home/CVE/CODESYS Gateway 3 before 3.5.16.70 has a NULL pointer dereference that may result in a denial of service (DoS).
CVE

CVE-2021-29241

CODESYS Gateway 3 before 3.5.16.70 has a NULL pointer dereference that may result in a denial of service (DoS).

CODESYS Gateway 3 before 3.5.16.70 has a NULL pointer dereference that may result in a denial of service (DoS).

HIGH · CVSS 7.5 EPSS 0.00407
Schedule remediation
  • CVSS base score ≥ 7.0
Sigma rules1 YARA rules0
⬡

Weakness Classification

CWE-476NULL Pointer Dereference
▤

Affected Products & Versions

12
codesys control for beaglebone sl>= 3.0 and < 4.0.1.0
codesys control for empc-a\/imx6 sl>= 3.0 and < 4.0.1.0
codesys control for iot2000 sl>= 3.0 and < 4.0.1.0
codesys control for linux sl>= 3.0 and < 4.0.1.0
codesys control for pfc100 sl>= 3.0 and < 3.5.16.0
codesys control for pfc200 sl>= 3.0 and < 3.5.16.0
codesys control for raspberry pi sl>= 3.0 and < 4.0.1.0
codesys control runtime system toolkit>= 3.0 and < 3.5.16.70
◈

Sigma Hunt Rules

1
Exact rules name this CVE ID. Product rules name an affected product in their title. Related rules cover techniques used by actors who exploited this CVE. Showing the most relevant matches; the complete related set is on the full drill-down.
productmediumAzure Application Gateway Modified or Deleted
▣

Scoring & Timeline

7.5
HIGH · CVSS v3.1 · cve@mitre.org
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD03 May 2021 · 02:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
⚑

Vendor Advisories

2
cisa-csafcisa-csaf-csaf_files-OT-white-2025-icsa-25-273-04
cisa-csafcisa-csaf-csaf_files-OT-white-2026-icsa-26-076-01
🔗

References & Sources

3
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://customers.codesys.com/index.phpPermissions RequiredVendor Advisory
https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=14637&token=8dbd75ae7553ae3be25e22f741db783b31e14799&download=Vendor Advisory
https://www.codesys.com/security/security-reports.htmlVendor Advisory
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