How severe is CVE-2020-15786?

CVE-2020-15786 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-15786 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-15786?

CVE-2020-15786 primarily affects Siemens Simatic Hmi Basic Panels 2nd Generation Firmware. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-15786?

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

When was CVE-2020-15786 published?

CVE-2020-15786 was published on 2020-09-09 and last updated on 2026-06-17.

CVE-2020-15786

CVE-2020-15786 is a critical-severity vulnerability in Siemens Simatic Hmi Basic Panels 2nd Generation Firmware with a CVSS 3.x base score of 9.8. 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-307.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 5.0
EPSS exploit prediction: 1% (71st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-307
Affected product: Siemens Simatic Hmi Basic Panels 2nd Generation Firmware
Published: 2020-09-09
Last modified: 2026-06-17

Description

A vulnerability has been identified in SIMATIC HMI Basic Panels 2nd Generation (incl. SIPLUS variants) (All versions < V16), SIMATIC HMI Comfort Panels (incl. SIPLUS variants) (All versions <= V16), SIMATIC HMI Mobile Panels (All versions <= V16), SIMATIC HMI Unified Comfort Panels (All versions <= V16). Affected devices insufficiently block excessive authentication attempts. This could allow a remote attacker to discover user passwords and obtain access to the Sm@rt Server via a brute-force attack.

Frequently asked questions

What is CVE-2020-15786?: A vulnerability has been identified in SIMATIC HMI Basic Panels 2nd Generation (incl. SIPLUS variants) (All versions < V16), SIMATIC HMI Comfort Panels (incl. SIPLUS variants) (All versions <= V16), SIMATIC HMI Mobile Panels (All versions <= V16), SIMATIC HMI Unified Comfort Panels (All versions <= V16). Affected devices insufficiently block excessive authentication attempts. This could allow a remote attacker to discover user passwords and obtain access to the Sm@rt Server via a brute-force attack.
How severe is CVE-2020-15786?: CVE-2020-15786 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-15786 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-15786?: CVE-2020-15786 primarily affects Siemens Simatic Hmi Basic Panels 2nd Generation Firmware. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-15786?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2020-15786 published?: CVE-2020-15786 was published on 2020-09-09 and last updated on 2026-06-17.

References

https://cert-portal.siemens.com/productcert/pdf/ssa-542525.pdf

Affected products (4)

cpe:2.3:o:siemens:simatic_hmi_basic_panels_2nd_generation_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_hmi_comfort_panels_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_hmi_mobile_panels_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_hmi_united_comfort_panels_firmware:*:*:*:*:*:*:*:*

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