How severe is CVE-2021-27427?

CVE-2021-27427 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2021-27427 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-27427?

CVE-2021-27427 affects Riot-os Riot. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-27427?

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-2021-27427 published?

CVE-2021-27427 was published on 2022-05-03 and last updated on 2026-06-17.

CVE-2021-27427

CVE-2021-27427 is a high-severity vulnerability in Riot-os Riot with a CVSS 3.x base score of 7.3. 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-190.

Key facts

Severity: High (CVSS 3.x base score 7.3)
CVSS v2: 7.5
EPSS exploit prediction: 2% (72nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-190
Affected product: Riot-os Riot
Published: 2022-05-03
Last modified: 2026-06-17

Description

RIOT OS version 2020.01.1 is vulnerable to integer wrap-around in its implementation of calloc function, which can lead to arbitrary memory allocation, resulting in unexpected behavior such as a crash or a remote code injection/execution.

Frequently asked questions

What is CVE-2021-27427?: RIOT OS version 2020.01.1 is vulnerable to integer wrap-around in its implementation of calloc function, which can lead to arbitrary memory allocation, resulting in unexpected behavior such as a crash or a remote code injection/execution.
How severe is CVE-2021-27427?: CVE-2021-27427 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2021-27427 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27427?: CVE-2021-27427 affects Riot-os Riot. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-27427?: 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-2021-27427 published?: CVE-2021-27427 was published on 2022-05-03 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:riot-os:riot:2020.01.1:*:*:*:*:*:*:*

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