CVE-2026-3509

highpriority · track · 0EPSS 0.006 · 48 %ileDEEU
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.60% (48th) EPSS
CVSS 7.5 · high
Is it mine?
49 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · cert_bund · codesys_psirt

EPSS · scored 2026-10-22

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.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

  • Fixedcodesys_psirt

    Update the following products to version 3.5.22.0. * CODESYS Control RTE (SL) * CODESYS Control RTE (for Beckhoff CX) SL * CODESYS Control Win (SL) * CODESYS Runtime Toolkit The CODESYS Development System and the products available as CODESYS add-ons can be downloaded and installed directly with the CODESYS Installer or be downloaded from the CODESYS Store. Alternatively, as well as for all other products, you will find further information on obtaining the software update in the CODESYS Update area https://www.codesys.com/download/.

  • Mitigationcodesys_psirt

    As a mitigation, the Audit Log feature can be disabled in the CODESYS Control runtime configuration file. When the Audit Log logger is not enabled, the affected functionality is no longer exposed and the vulnerability cannot be exploited. To disable the Audit Log feature, use the following settings. Depending on your existing configuration, the logger index may vary. [CmpLog] Logger.0.Name=.Audit.log Logger.0.Enable=0

02

cvss

Technical severity, 0–10. One row per scoring source.

7.5
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.5

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · info@cert.vde.comexploitability 3.9 · impact 3.6
v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · CODESYS PSIRT
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-134USCWE-134US
05

affected products (49)

Products and version ranges known to be affected.

showing 20 of 49
06

advisories (2)

Vendor and ecosystem advisories describing this.

  • Advisory2026-03_VDE-2026-018CODESYS Control V3 - Externally-controlled format string in Auditlog2026-03-24csaf · codesys_psirtDE

    The CODESYS Control runtime system's CmpAuditLog component allows potentially unauthenticated remote attackers to control the format string of processed log messages. Due to the internal processing logic, the impact is limited to a crash of the CODESYS Control runtime.

  • WID-SEC-W-2026-0832CODESYS: Mehrere SchwachstellenDeutsch2026-03-23csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in CODESYS ausnutzen, um beliebigen Programmcode auszuführen, und um einen Denial of Service Angriff durchzuführen.

07

also known as (3)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdcert_bundcodesys_psirtNVDCVE.orgMITRE
published 2026-03-24modified 2026-06-17
09

references (4)

External citations — patches, advisories, analysis.

scry

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