CVE-2026-14366

Device crash via caller-owned packet double unref

Published Aug 31, 2026 · Updated Sep 1, 2026

Use-after-free in Zephyr RTOS 4.1.0 through 4.4.0 allows adjacent attackers to crash devices via ordinary SiWx917 WiFi traffic. The siwx91x_send callback drops the caller-owned transmit packet reference, after which ethernet_send reads and unrefs the prematurely freed packet again. The native-stack path is built by default; concurrent packet-slot reuse can corrupt a live packet and produce transmit hangs or crashes.

CVSS severity6.4
Medium
EPSS probability0.16%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in Zephyr RTOS 4.1.0 through 4.4.0 allows adjacent attackers to crash devices via ordinary SiWx917 WiFi traffic. The siwx91x_send callback drops the caller-owned transmit packet reference, after which ethernet_send reads and unrefs the prematurely freed packet again. The native-stack path is built by default; concurrent packet-slot reuse can corrupt a live packet and produce transmit hangs or crashes.

The record

CVE
CVE-2026-14366
Published
Aug 31, 2026
Updated
Sep 1, 2026
Vendor
Zephyr Project
Product
Zephyr RTOS
Classifications
CWE-416, T1499
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 31, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 1, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=4.1.0 <4.4.2

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

Zephyr Project · Zephyr RTOSversion=4.1.0 <4.4.2

Published CVSS scores

6.4Zephyr ProjectCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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