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7.5
HIGH CVSS 3.1
CVE-2026-3509
CODESYS Control Audit Log Format String DoS
Overview
Description

An unauthenticated remote attacker may be able to control the format string of messages processed by the Audit Log of the CODESYS Control runtime system, potentially resulting in a denial‑of‑service (DoS) condition.

Details
INFO

Published Date :

March 24, 2026, 8:16 a.m.

Last Modified :

June 17, 2026, 10:43 a.m.

Remotely Exploit :

Yes !

Source :

[email protected]
Impact
Affected Products

The following products are affected by CVE-2026-3509 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Codesys runtime_toolkit
2 Codesys control_for_beaglebone_sl
3 Codesys control_for_empc-a\/imx6_sl
4 Codesys control_for_iot2000_sl
5 Codesys control_for_linux_sl
6 Codesys control_for_pfc100_sl
7 Codesys control_for_pfc200_sl
8 Codesys control_for_plcnext_sl
9 Codesys control_for_raspberry_pi_sl
10 Codesys control_for_wago_touch_panels_600_sl
11 Codesys control_for_linux_arm_sl
12 Codesys control_rte_\(for_beckhoff_cx\)_sl
13 Codesys control_rte_\(sl\)
14 Codesys control_win_\(sl\)
15 Codesys virtual_control_sl
: Total Affected Vendor : 1 | Products : 15
Scoring
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 HIGH 270ccfa6-a436-4e77-922e-914ec3a9685c
CVSS 3.1 HIGH [email protected]
Solution
Apply security updates for CODESYS Control runtime system to fix audit log format string vulnerability.
  • Apply security updates for the affected software.
  • Update the CODESYS Control runtime system.
  • Configure audit log message processing securely.
References
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-3509.

URL Resource
https://certvde.com/de/advisories/VDE-2026-018
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-3509 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-3509 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-3509 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2026-3509 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by [email protected]

    Jun. 17, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'CODESYS', 'product': 'CODESYS Control RTE (SL)', 'versions': [{'status': 'affected', 'version': '3.5.17.0', 'lessThan': '3.5.22.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}, {'vendor': 'CODESYS', 'product': 'CODESYS Control RTE (for Beckhoff CX) SL', 'versions': [{'status': 'affected', 'version': '3.5.17.0', 'lessThan': '3.5.22.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}, {'vendor': 'CODESYS', 'product': 'CODESYS Control Win (SL)', 'versions': [{'status': 'affected', 'version': '3.5.17.0', 'lessThan': '3.5.22.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}, {'vendor': 'CODESYS', 'product': 'CODESYS Runtime Toolkit', 'versions': [{'status': 'affected', 'version': '3.5.17.0', 'lessThan': '3.5.22.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}, {'vendor': 'CODESYS', 'product': 'CODESYS Control for BeagleBone SL', 'versions': [{'status': 'affected', 'version': '4.1.0.0', 'lessThan': '4.21.0.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}, {'vendor': 'CODESYS', 'product': 'CODESYS Control for emPC-A/iMX6 SL', 'versions': [{'status': 'affected', 'version': '4.1.0.0', 'lessThan': '4.21.0.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}, {'vendor': 'CODESYS', 'product': 'CODESYS Control for IOT2000 SL', 'versions': [{'status': 'affected', 'version': '4.1.0.0', 'lessThan': '4.21.0.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}, {'vendor': 'CODESYS', 'product': 'CODESYS Control for Linux ARM SL', 'versions': [{'status': 'affected', 'version': '4.1.0.0', 'lessThan': '4.21.0.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}, {'vendor': 'CODESYS', 'product': 'CODESYS Control for Linux SL', 'versions': [{'status': 'affected', 'version': '4.1.0.0', 'lessThan': '4.21.0.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}, {'vendor': 'CODESYS', 'product': 'CODESYS Control for PFC100 SL', 'versions': [{'status': 'affected', 'version': '4.1.0.0', 'lessThan': '4.21.0.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}, {'vendor': 'CODESYS', 'product': 'CODESYS Control for PFC200 SL', 'versions': [{'status': 'affected', 'version': '4.1.0.0', 'lessThan': '4.21.0.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}, {'vendor': 'CODESYS', 'product': 'CODESYS Control for PLCnext SL', 'versions': [{'status': 'affected', 'version': '4.1.0.0', 'lessThan': '4.21.0.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}, {'vendor': 'CODESYS', 'product': 'CODESYS Control for Raspberry Pi SL', 'versions': [{'status': 'affected', 'version': '4.1.0.0', 'lessThan': '4.21.0.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}, {'vendor': 'CODESYS', 'product': 'CODESYS Control for WAGO Touch Panels 600 SL', 'versions': [{'status': 'affected', 'version': '4.1.0.0', 'lessThan': '4.21.0.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}, {'vendor': 'CODESYS', 'product': 'CODESYS Virtual Control SL', 'versions': [{'status': 'affected', 'version': '4.1.0.0', 'lessThan': '4.21.0.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}]
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jun. 17, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-3509', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-03-26T12:35:33.893071Z'}
  • New CVE Received by [email protected]

    Mar. 24, 2026

    Action Type Old Value New Value
    Added Description An unauthenticated remote attacker may be able to control the format string of messages processed by the Audit Log of the CODESYS Control runtime system, potentially resulting in a denial‑of‑service (DoS) condition.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-134
    Added Reference https://certvde.com/de/advisories/VDE-2026-018
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CVSS
Vulnerability Scoring Details
Base CVSS Score: 7.5
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact