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EPSS 0.4%top 72%

CVE-2026-3509: CWE-134 Use of Externally-Controlled Format String in CODESYS CODESYS Control RTE (SL)

0
High
VulnerabilityCVE-2026-3509cvecve-2026-3509cwe-134
Published: 03/24/2026 (03/24/2026, 07:42:33 UTC)
Source: CVE Database V5
Vendor/Project: CODESYS
Product: CODESYS Control RTE (SL)

Description

CVE-2026-3509 is a high-severity vulnerability in CODESYS Control RTE (SL) version 3.5.17.0. It involves an unauthenticated remote attacker potentially controlling the format string of messages processed by the Audit Log, which can lead to a denial-of-service (DoS) condition. The vulnerability does not impact confidentiality or integrity but affects availability. No patch or official fix information is provided in the available data.

CVSS v3.1

Score 7.5high

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected software

GitHub Actionsmore threats →ai
codesys/CODESYS-Control-RTE-SL
pkg:github/codesys/CODESYS-Control-RTE-SL
Affected versions
=3.5.17.0

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AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 06/18/2026, 18:30:31 UTC

Technical Analysis

This vulnerability (CWE-134) in CODESYS Control RTE (SL) version 3.5.17.0 allows an unauthenticated remote attacker to manipulate the format string used in Audit Log message processing. Such control over format strings can cause the system to crash or become unresponsive, resulting in a denial-of-service condition. The CVSS 3.1 base score is 7.5, reflecting network attack vector, low attack complexity, no privileges or user interaction required, and impact limited to availability.

Potential Impact

An attacker can cause a denial-of-service (DoS) by exploiting the format string vulnerability in the Audit Log processing component. There is no impact on confidentiality or integrity according to the CVSS vector. The system availability is affected, potentially disrupting operations relying on CODESYS Control RTE (SL) 3.5.17.0.

Mitigation Recommendations

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch information is available in the provided data. Until a patch is available, monitor vendor communications for updates and consider restricting network access to the affected system to reduce exposure.

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Technical Details

Data Version
5.2
Assigner Short Name
CERTVDE
Date Reserved
2026-03-04T09:24:19.745Z
Cvss Version
3.1
State
PUBLISHED

Threat ID: 69c244c0f4197a8e3b01d2db

Added to database: 03/24/2026, 08:01:04 UTC

Last enriched: 06/18/2026, 18:30:31 UTC

Last updated: 07/31/2026, 19:22:58 UTC

Views: 204

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