CVE-2026-10666Public exploitNetwork attack vector

Remote code execution via oversized IPv4 port suffix

Published Jul 12, 2026 · Updated Jul 12, 2026

Stack buffer overflow in Zephyr RTOS 1.9.0 through 4.4.0 allows remote attackers to corrupt memory via a crafted IPv4 address-and-port string. parse_ipv4() copies the suffix after the colon into a 17-byte stack buffer using the unbounded input length instead of the destination size. Exposure requires an application to resolve a network-influenced address string; exploitation can crash the device or hijack control flow.

CVSS severity8.1
High
EPSS probability0.65%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack buffer overflow in Zephyr RTOS 1.9.0 through 4.4.0 allows remote attackers to corrupt memory via a crafted IPv4 address-and-port string. parse_ipv4() copies the suffix after the colon into a 17-byte stack buffer using the unbounded input length instead of the destination size. Exposure requires an application to resolve a network-influenced address string; exploitation can crash the device or hijack control flow.

The record

CVE
CVE-2026-10666
Published
Jul 12, 2026
Updated
Jul 12, 2026
Vendor
Zephyr Project
Product
Zephyr RTOS
Classifications
CWE-121
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 12, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 12, 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=1.9.0 <4.5.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Zephyr Project · Zephyr RTOSversion=1.9.0 <4.5.0

Published CVSS scores

8.1Zephyr ProjectCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-121Stack-based Buffer Overflow

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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