How severe is CVE-2021-31663?

CVE-2021-31663 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 high, integrity none, and availability none.

Is CVE-2021-31663 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-31663?

CVE-2021-31663 affects Riot-os Riot. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-31663?

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-2021-31663 published?

CVE-2021-31663 was published on 2021-06-18 and last updated on 2026-06-17.

CVE-2021-31663

CVE-2021-31663 is a high-severity vulnerability in Riot-os Riot 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-120.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Riot-os Riot
Published: 2021-06-18
Last modified: 2026-06-17

Description

RIOT-OS 2021.01 before commit bc59d60be60dfc0a05def57d74985371e4f22d79 contains a buffer overflow which could allow attackers to obtain sensitive information.

Frequently asked questions

What is CVE-2021-31663?: RIOT-OS 2021.01 before commit bc59d60be60dfc0a05def57d74985371e4f22d79 contains a buffer overflow which could allow attackers to obtain sensitive information.
How severe is CVE-2021-31663?: CVE-2021-31663 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 high, integrity none, and availability none.
Is CVE-2021-31663 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-31663?: CVE-2021-31663 affects Riot-os Riot. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-31663?: 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-2021-31663 published?: CVE-2021-31663 was published on 2021-06-18 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:riot-os:riot:2021.01:-:*:*:*:*:*:*

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