How severe is CVE-2021-40829?

CVE-2021-40829 has a CVSS 3.x base score of 6.3, rated medium severity. It is exploitable over an adjacent network with high attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-40829 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-40829?

CVE-2021-40829 primarily affects Amazon Amazon Web Services Internet Of Things Device Software Development Kit V2. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-40829?

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

When was CVE-2021-40829 published?

CVE-2021-40829 was published on 2021-11-23 and last updated on 2026-06-17.

CVE-2021-40829

CVE-2021-40829 is a medium-severity vulnerability in Amazon Amazon Web Services Internet Of Things Device Software Development Kit V2 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-295.

Key facts

Severity: Medium (CVSS 3.x base score 6.3)
CVSS v2: 5.8
EPSS exploit prediction: 0% (29th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Amazon Amazon Web Services Internet Of Things Device Software Development Kit V2
Published: 2021-11-23
Last modified: 2026-06-17

Description

Connections initialized by the AWS IoT Device SDK v2 for Java (versions prior to 1.4.2), Python (versions prior to 1.6.1), C++ (versions prior to 1.12.7) and Node.js (versions prior to 1.5.3) did not verify server certificate hostname during TLS handshake when overriding Certificate Authorities (CA) in their trust stores on MacOS. This issue has been addressed in aws-c-io submodule versions 0.10.5 onward. This issue affects: Amazon Web Services AWS IoT Device SDK v2 for Java versions prior to 1.4.2 on macOS. Amazon Web Services AWS IoT Device SDK v2 for Python versions prior to 1.6.1 on macOS. Amazon Web Services AWS IoT Device SDK v2 for C++ versions prior to 1.12.7 on macOS. Amazon Web Services AWS IoT Device SDK v2 for Node.js versions prior to 1.5.3 on macOS. Amazon Web Services AWS-C-IO 0.10.4 on macOS.

Frequently asked questions

What is CVE-2021-40829?: Connections initialized by the AWS IoT Device SDK v2 for Java (versions prior to 1.4.2), Python (versions prior to 1.6.1), C++ (versions prior to 1.12.7) and Node.js (versions prior to 1.5.3) did not verify server certificate hostname during TLS handshake when overriding Certificate Authorities (CA) in their trust stores on MacOS. This issue has been addressed in aws-c-io submodule versions 0.10.5 onward. This issue affects: Amazon Web Services AWS IoT Device SDK v2 for Java versions prior to 1.4.2 on macOS. Amazon Web Services AWS IoT Device SDK v2 for Python versions prior to 1.6.1 on macOS. Amazon Web Services AWS IoT Device SDK v2 for C++ versions prior to 1.12.7 on macOS. Amazon Web Services AWS IoT Device SDK v2 for Node.js versions prior to 1.5.3 on macOS. Amazon Web Services AWS-C-IO 0.10.4 on macOS.
How severe is CVE-2021-40829?: CVE-2021-40829 has a CVSS 3.x base score of 6.3, rated medium severity. It is exploitable over an adjacent network with high attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-40829 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-40829?: CVE-2021-40829 primarily affects Amazon Amazon Web Services Internet Of Things Device Software Development Kit V2. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-40829?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-40829 published?: CVE-2021-40829 was published on 2021-11-23 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:amazon:amazon_web_services_internet_of_things_device_software_development_kit_v2:*:*:*:*:*:java:*:*
cpe:2.3:a:amazon:amazon_web_services_internet_of_things_device_software_development_kit_v2:*:*:*:*:*:node.js:*:*
cpe:2.3:a:amazon:amazon_web_services_internet_of_things_device_software_development_kit_v2:*:*:*:*:*:python:*:*
cpe:2.3:a:amazon:amazon_web_services_internet_of_things_device_software_development_kit_v2:*:*:*:*:*:c\+\+:*:*

More vulnerabilities in Amazon Amazon Web Services Internet Of Things Device Software Development Kit V2

CVE-2021-40831 — Medium (CVSS 6.3): The AWS IoT Device SDK v2 for Java, Python, C++ and Node.js appends a user supplied Certificate Authority (CA) to the…
CVE-2021-40830 — Medium (CVSS 6.3): The AWS IoT Device SDK v2 for Java, Python, C++ and Node.js appends a user supplied Certificate Authority (CA) to the…
CVE-2021-40828 — Medium (CVSS 6.3): Connections initialized by the AWS IoT Device SDK v2 for Java (versions prior to 1.3.3), Python (versions prior to…

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