How severe is CVE-2021-22547?

CVE-2021-22547 has a CVSS 3.x base score of 6.3, rated medium severity. It is exploitable over local access with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2021-22547 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-22547?

CVE-2021-22547 affects Google Cloud Iot Device Sdk For Embedded C. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-22547?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-22547 published?

CVE-2021-22547 was published on 2021-05-04 and last updated on 2026-06-17.

CVE-2021-22547

CVE-2021-22547 is a medium-severity vulnerability in Google Cloud Iot Device Sdk For Embedded C with a CVSS 3.x base score of 6.3. 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-120.

Key facts

Severity: Medium (CVSS 3.x base score 6.3)
CVSS v2: 4.6
EPSS exploit prediction: 0% (12th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Google Cloud Iot Device Sdk For Embedded C
Published: 2021-05-04
Last modified: 2026-06-17

Description

In IoT Devices SDK, there is an implementation of calloc() that doesn't have a length check. An attacker could pass in memory objects larger than the buffer and wrap around to have a smaller buffer than required, allowing the attacker access to the other parts of the heap. We recommend upgrading the Google Cloud IoT Device SDK for Embedded C used to 1.0.3 or greater.

Frequently asked questions

What is CVE-2021-22547?: In IoT Devices SDK, there is an implementation of calloc() that doesn't have a length check. An attacker could pass in memory objects larger than the buffer and wrap around to have a smaller buffer than required, allowing the attacker access to the other parts of the heap. We recommend upgrading the Google Cloud IoT Device SDK for Embedded C used to 1.0.3 or greater.
How severe is CVE-2021-22547?: CVE-2021-22547 has a CVSS 3.x base score of 6.3, rated medium severity. It is exploitable over local access with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2021-22547 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-22547?: CVE-2021-22547 affects Google Cloud Iot Device Sdk For Embedded C. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-22547?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-22547 published?: CVE-2021-22547 was published on 2021-05-04 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:google:cloud_iot_device_sdk_for_embedded_c:*:*:*:*:*:*:*:*

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