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Fencer Intel
high 7.5

CVE-2026-3509 json

CODESYS Control Audit Log Format String DoS

published 7mo ago modified 4mo ago also EUVD-2026-14784

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 29%
public exploits
0
none known

Summary

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.

Patch / fix

  • CODESYS CODESYS Control RTE (SL) 3.5.22.0
  • CODESYS CODESYS Control RTE (for Beckhoff CX) SL 3.5.22.0
  • CODESYS CODESYS Control Win (SL) 3.5.22.0
  • CODESYS CODESYS Runtime Toolkit 3.5.22.0
  • CODESYS CODESYS Control for BeagleBone SL 4.21.0.0
  • CODESYS CODESYS Control for emPC-A/iMX6 SL 4.21.0.0
  • CODESYS CODESYS Control for IOT2000 SL 4.21.0.0
  • CODESYS CODESYS Control for Linux ARM SL 4.21.0.0
  • CODESYS CODESYS Control for Linux SL 4.21.0.0
  • CODESYS CODESYS Control for PFC100 SL 4.21.0.0
  • CODESYS CODESYS Control for PFC200 SL 4.21.0.0
  • CODESYS CODESYS Control for PLCnext SL 4.21.0.0
  • CODESYS CODESYS Control for Raspberry Pi SL 4.21.0.0
  • CODESYS CODESYS Control for WAGO Touch Panels 600 SL 4.21.0.0
  • CODESYS CODESYS Virtual Control SL 4.21.0.0

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CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
7mo ago

Exploit prediction

0.36% chance of exploitation in the next 30 days, higher than 29% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

  • CODESYS CODESYS Control RTE (SL)
  • CODESYS CODESYS Control RTE (for Beckhoff CX) SL
  • CODESYS CODESYS Control Win (SL)
  • CODESYS CODESYS Runtime Toolkit
  • CODESYS CODESYS Control for BeagleBone SL
  • CODESYS CODESYS Control for emPC-A/iMX6 SL
  • CODESYS CODESYS Control for IOT2000 SL
  • CODESYS CODESYS Control for Linux ARM SL
  • CODESYS CODESYS Control for Linux SL
  • CODESYS CODESYS Control for PFC100 SL
  • CODESYS CODESYS Control for PFC200 SL
  • CODESYS CODESYS Control for PLCnext SL
  • CODESYS CODESYS Control for Raspberry Pi SL
  • CODESYS CODESYS Control for WAGO Touch Panels 600 SL
  • CODESYS CODESYS Virtual Control SL

Classification

Weakness
  • CWE-134 Use of Externally-Controlled Format String

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.