How severe is CVE-2017-9938?

CVE-2017-9938 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2017-9938 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-9938?

CVE-2017-9938 affects Siemens Simatic Logon. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2017-9938?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2017-9938 published?

CVE-2017-9938 was published on 2017-08-08 and last updated on 2026-06-17.

CVE-2017-9938

CVE-2017-9938 is a high-severity vulnerability in Siemens Simatic Logon with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Siemens Simatic Logon
Published: 2017-08-08
Last modified: 2026-06-17

Description

A vulnerability was discovered in Siemens SIMATIC Logon (All versions before V1.6) that could allow specially crafted packets sent to the SIMATIC Logon Remote Access service on port 16389/tcp to cause a Denial-of-Service condition. The service restarts automatically.

Frequently asked questions

What is CVE-2017-9938?: A vulnerability was discovered in Siemens SIMATIC Logon (All versions before V1.6) that could allow specially crafted packets sent to the SIMATIC Logon Remote Access service on port 16389/tcp to cause a Denial-of-Service condition. The service restarts automatically.
How severe is CVE-2017-9938?: CVE-2017-9938 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2017-9938 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-9938?: CVE-2017-9938 affects Siemens Simatic Logon. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2017-9938?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2017-9938 published?: CVE-2017-9938 was published on 2017-08-08 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:siemens:simatic_logon:*:sp3_update_2:*:*:*:*:*:*

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