23 Oct 2026 15:48:27 UTC
Improper validation of certificate with host mismatch in AWS IoT Device SDK for Python
cve-program · CVE-2026-92943 · Published
CVE-2026-92943
Improper validation of certificate with host mismatch in AWS IoT Device SDK for Python
CVSS 3.1 8.1 HIGHCVSS 4.0 9.2 CRITICALCheck source for fixed versionsKEV status unknown
cve-program · CVE-2026-92943
PublishedImproper 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.
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