CVE-2026-10638Network attack vector

Remote crash via post-send interface dereference

Published Jun 16, 2026 · Updated Jun 16, 2026

Use-after-free in the ICMPv6 networking path in Zephyr RTOS allows remote attackers to crash devices via crafted IPv6 traffic. After net_try_send_data() takes ownership and can free a packet, two ICMPv6 handlers call net_pkt_iface() on it to update statistics. A network-reachable build with CONFIG_NET_NATIVE_IPV6 is exposed; per-interface statistics converts the stale interface read into a pointer write, so impact also includes memory corruption.

CVSS severity5.9
Medium
EPSS probability0.35%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Use-after-free in the ICMPv6 networking path in Zephyr RTOS allows remote attackers to crash devices via crafted IPv6 traffic. After net_try_send_data() takes ownership and can free a packet, two ICMPv6 handlers call net_pkt_iface() on it to update statistics. A network-reachable build with CONFIG_NET_NATIVE_IPV6 is exposed; per-interface statistics converts the stale interface read into a pointer write, so impact also includes memory corruption.

The record

CVE
CVE-2026-10638
Published
Jun 16, 2026
Updated
Jun 16, 2026
Vendor
Zephyr Project
Product
Zephyr RTOS
Classifications
CWE-416, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 16, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 16, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=4.2.0 <4.5.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Zephyr Project · Zephyr RTOSversion=4.2.0 <4.5.0

Published CVSS scores

5.9Zephyr ProjectCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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 exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo