Vulnerabilities

Vulnerability · CVE-2026-3509

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 r…

Published Mar 24, 2026 · catalog updated Jun 17, 2026 · the affected product

Last checked Nov 10, 2026. A connected source was read within the last 7 days.

Check if you run it

No confirmed exploitation is on record for CVE-2026-3509. EPSS is 0.37%. Act only if a listed version of the affected product is installed.

Gaps on this record

  • No plain product name is stored. The page cannot tell you which product to check.
  • No version range is stored. A customer cannot check an installed version against this record.
  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
High7.5
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.37%
Remediation
Not established
Affected products
See sources for product scope

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.

No affected version ranges are stored yet. Use the vendor advisory before you decide this record does not apply.

How to fix CVE-2026-3509

  • No stored fix

    No vendor fix text is stored. Use the linked advisory before you change production.

  • Version check

    No version range is stored, so an installed version cannot be checked on this page.

  • Advisory

    Open the cve_org record and follow its fix.

  • Official advisories

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2026-3509. EPSS is 0.37%. Act only if a listed version of the affected product is installed.

Which versions are affected?

Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-134: Format String Vulnerability. EPSS 0.37%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Mar 24, 2026 · NIST NVD

    Detected

    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.

  2. Jun 17, 2026 · NIST NVD

    Updated

    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.

Sources

  • CVE.orgVulnerability recordCVE-2026-3509

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2026-3509

    30-day exploitation probability 0.37%

    first.org
  • NIST NVDVulnerability recordCVE-2026-3509

    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.

    nvd.nist.gov

References

Freshness

Last verified in this catalog Nov 10, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.

  • FIRST EPSSNov 10, 2026
  • CVE.orgOct 16, 2026
  • NIST NVDOct 15, 2026