How severe is CVE-2021-20988?

CVE-2021-20988 has a CVSS 3.x base score of 8.6, 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-2021-20988 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20988?

CVE-2021-20988 primarily affects Hilscher Rcx Rtos. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-20988?

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-2021-20988 published?

CVE-2021-20988 was published on 2021-05-13 and last updated on 2026-06-17.

CVE-2021-20988

CVE-2021-20988 is a high-severity vulnerability in Hilscher Rcx Rtos with a CVSS 3.x base score of 8.6. 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-119.

Key facts

Severity: High (CVSS 3.x base score 8.6)
CVSS v2: 5.0
EPSS exploit prediction: 1% (61st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-119
Affected product: Hilscher Rcx Rtos
Published: 2021-05-13
Last modified: 2026-06-17

Description

In Hilscher rcX RTOS versions prios to V2.1.14.1 the actual UDP packet length is not verified against the length indicated by the packet. This may lead to a denial of service of the affected device.

Frequently asked questions

What is CVE-2021-20988?: In Hilscher rcX RTOS versions prios to V2.1.14.1 the actual UDP packet length is not verified against the length indicated by the packet. This may lead to a denial of service of the affected device.
How severe is CVE-2021-20988?: CVE-2021-20988 has a CVSS 3.x base score of 8.6, 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-2021-20988 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20988?: CVE-2021-20988 primarily affects Hilscher Rcx Rtos. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-20988?: 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-2021-20988 published?: CVE-2021-20988 was published on 2021-05-13 and last updated on 2026-06-17.

References

Affected products (9)

cpe:2.3:a:hilscher:rcx_rtos:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:ice1-16di-g60l-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:ice1-16dio-g60l-c1-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:ice1-16dio-g60l-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:ice1-8di8do-g60l-c1-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:ice1-8di8do-g60l-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:ice1-8iol-g30l-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:ice1-8iol-g60l-v1d_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:pepperl-fuchs:ice1-8iol-s2-g60l-v1d_firmware:*:*:*:*:*:*:*:*

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