How severe is CVE-2021-20986?

CVE-2021-20986 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-2021-20986 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20986?

CVE-2021-20986 primarily affects Hilscher Profinet Io Device Firmware. In total, 24 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-20986?

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-2021-20986 published?

CVE-2021-20986 was published on 2021-02-16 and last updated on 2026-06-17.

CVE-2021-20986

CVE-2021-20986 is a high-severity vulnerability in Hilscher Profinet Io Device 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-787.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (59th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Hilscher Profinet Io Device Firmware
Published: 2021-02-16
Last modified: 2026-06-17

Description

A Denial of Service vulnerability was found in Hilscher PROFINET IO Device V3 in versions prior to V3.14.0.7. This may lead to unexpected loss of cyclic communication or interruption of acyclic communication.

Frequently asked questions

What is CVE-2021-20986?: A Denial of Service vulnerability was found in Hilscher PROFINET IO Device V3 in versions prior to V3.14.0.7. This may lead to unexpected loss of cyclic communication or interruption of acyclic communication.
How severe is CVE-2021-20986?: CVE-2021-20986 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-2021-20986 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20986?: CVE-2021-20986 primarily affects Hilscher Profinet Io Device Firmware. In total, 24 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-20986?: 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-2021-20986 published?: CVE-2021-20986 was published on 2021-02-16 and last updated on 2026-06-17.

References

Affected products (24)

cpe:2.3:o:hilscher:profinet_io_device_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pgv100-f200a-b17-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pgv150i-f200a-b17-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pgv100-f200-b17-v1d-7477_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pxv100-f200-b17-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pxv100-f200-b17-v1d-3636_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pcv80-f200-b17-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pcv100-f200-b17-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pcv50-f200-b17-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pcv100-f200-b17-v1d-6011-6997_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pcv100-f200-b17-v1d-6011_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pcv100-f200-b17-v1d-6011-8203_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pxv100a-f200-b28-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pxv100a-f200-b28-v1d-6011_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pgv100a-f200-b28-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pgv100a-f200a-b28-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pgv100aq-f200a-b28-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pgv100aq-f200-b28-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pxv100aq-f200-b28-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pxv100aq-f200-b28-v1d-6011_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:ohv-f230-b17_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:oit500-f113b17-cb_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:pha_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:wcs_firmware:*:*:*:*:*:*:*:*

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