CVE-2026-92943 (CVSS 8.1)

Description

Improper validation of certificate with host mismatch in the MQTT client TLS connection layer in AWS IoT Device SDK for Python 1.5.3 through 1.6.0 on Python 3.7 and later might allow an adversary-in-the-middle actor to impersonate the AWS IoT Core endpoint, read device telemetry, and inject arbitrary MQTT messages that the device processes as authentic, via a certificate issued for an unrelated hostname by a certificate authority present in the device trust store. To remediate this issue, users should upgrade to version 1.6.1.

Is your site exposed to CVE-2026-92943?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

8.1

HIGH

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0038

Probability of exploitation

0.30%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-297 CWE-297

References

Other References

https://aws.amazon.com/security/security-bulletins/2026-114-aws/ https://github.com/aws/aws-iot-device-sdk-python/releases/tag/v1.6.1 https://github.com/aws/aws-iot-device-sdk-python/security/advisories/GHSA-g7vp-3rxx-v25r https://pypi.org/project/AWSIoTPythonSDK/1.6.1/

Frequently Asked Questions

What is CVE-2026-92943? +

Improper validation of certificate with host mismatch in the MQTT client TLS connection layer in AWS IoT Device SDK for Python 1.5.3 through 1.6.0 on Python 3.7 and later might allow an adversary-in-the-middle actor to impersonate the AWS IoT Core endpoint, read device telemetry, and inject arbitrary MQTT messages that the device processes as authentic, via a certificate issued for an unrelated hostname by a certificate authority present in the device trust store. To remediate this issue, users should upgrade to version 1.6.1. It has a CVSS v3.1 base score of 8.1 (HIGH).

How severe is CVE-2026-92943? +

CVE-2026-92943 has a CVSS v3.1 score of 8.1 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0038, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-92943? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2024-2462

Allow attackers to intercept or falsify data exchanges between the client and the server

CVE-2026-59638

In Bouncy Castle for Java before 1.85, JSSE hostname verifier CN-fallback enabled by default despite documented opt-in. This issue also …

CVE-2026-44467

The Claude Desktop app gives you Claude Code with a graphical interface built for running multiple sessions side by side. …

CVE-2026-15243

Apereo CAS Client accepts any CA-trusted certificate for any hostname, provided the URL the client is calling matches the configured …

CVE-2026-84197

In Eclipse Ditto's Node.js JavaScript client, all released versions of @eclipse-ditto/ditto-javascript-client-node from 2.0.0 to 3.9.0 and of its predecessor package …

CVE-2026-19553

ssl.SSLContext.wrap_bio() didn't require the server_hostname argument to not be None if ssl.SSLContext.check_hostname was set. Due to a missing parameter check …

CVE-2026-92943