How severe is CVE-2016-3949?

CVE-2016-3949 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-2016-3949 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-3949?

CVE-2016-3949 primarily affects Siemens Simatic S7-300 With Profitnet Support Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-3949?

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-2016-3949 published?

CVE-2016-3949 was published on 2016-06-27 and last updated on 2026-06-17.

CVE-2016-3949

CVE-2016-3949 is a high-severity vulnerability in Siemens Simatic S7-300 With Profitnet Support Firmware 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-399.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 4% (90th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-399
Affected product: Siemens Simatic S7-300 With Profitnet Support Firmware
Published: 2016-06-27
Last modified: 2026-06-17

Description

Siemens SIMATIC S7-300 Profinet-enabled CPU devices with firmware before 3.2.12 and SIMATIC S7-300 Profinet-disabled CPU devices with firmware before 3.3.12 allow remote attackers to cause a denial of service (defect-mode transition) via crafted (1) ISO-TSAP or (2) Profibus packets.

Frequently asked questions

What is CVE-2016-3949?: Siemens SIMATIC S7-300 Profinet-enabled CPU devices with firmware before 3.2.12 and SIMATIC S7-300 Profinet-disabled CPU devices with firmware before 3.3.12 allow remote attackers to cause a denial of service (defect-mode transition) via crafted (1) ISO-TSAP or (2) Profibus packets.
How severe is CVE-2016-3949?: CVE-2016-3949 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-2016-3949 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-3949?: CVE-2016-3949 primarily affects Siemens Simatic S7-300 With Profitnet Support Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-3949?: 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-2016-3949 published?: CVE-2016-3949 was published on 2016-06-27 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:o:siemens:simatic_s7-300_with_profitnet_support_firmware:3.2.11:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-300_without_profitnet_support_firmware:3.3.11:*:*:*:*:*:*:*

Other CWE-399 (Resource Management Errors) vulnerabilities

CVE-2015-8104 — Critical (CVSS 10.0): The KVM subsystem in the Linux kernel through 4.2.6, and Xen 4.3.x through 4.6.x, allows guest OS users to cause a…
CVE-2015-0339 — Critical (CVSS 10.0): Adobe Flash Player before 13.0.0.277 and 14.x through 17.x before 17.0.0.134 on Windows and OS X and before…
CVE-2015-0335 — Critical (CVSS 10.0): Adobe Flash Player before 13.0.0.277 and 14.x through 17.x before 17.0.0.134 on Windows and OS X and before…
CVE-2015-0333 — Critical (CVSS 10.0): Adobe Flash Player before 13.0.0.277 and 14.x through 17.x before 17.0.0.134 on Windows and OS X and before…
CVE-2014-4121 — Critical (CVSS 10.0): Microsoft .NET Framework 2.0 SP2, 3.5, 3.5.1, 4, 4.5, 4.5.1, and 4.5.2 does not properly parse internationalized…
CVE-2014-0560 — Critical (CVSS 10.0): Use-after-free vulnerability in Adobe Reader and Acrobat 10.x before 10.1.12 and 11.x before 11.0.09 on Windows and OS…

Browse all CWE-399 (Resource Management Errors) vulnerabilities →