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CVE-2026-87121

Description

A flaw was found in lwIP’s MQTT client. When parsing malformed MQTT fixed headers, the client can write beyond its receive buffer. A remote peer supplying crafted MQTT traffic could cause a client crash or potentially execute arbitrary code on the device. The reported affected versions are 2.0.1 through 2.2.1 inclusive.

Statement

Red Hat Product Security has determined that this vulnerability does not affect any currently supported Red Hat product. This assessment may evolve based on further analysis and discovery. For more information about this vulnerability and the products it affects, please see the linked references.

Mitigation

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

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