CVE-2026-7007Public exploit

Device crash via zero ext2 superblock divisors

Published Jul 24, 2026 · Updated Jul 24, 2026

Divide by zero in Zephyr RTOS 3.5.0 through 4.4.1 allows physically proximate attackers to crash devices via crafted ext2 media. ext2_verify_disk_superblock() accepts zero group-size fields that get_ngroups() and get_itable_entry() later use as divisors during mounting. Exploitation requires an attacker-controlled image and a device using Zephyr's in-tree ext2 filesystem; affected Cortex-M targets raise a fatal UsageFault.

CVSS severity4.6
Medium
EPSS probability0.22%
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

Divide by zero in Zephyr RTOS 3.5.0 through 4.4.1 allows physically proximate attackers to crash devices via crafted ext2 media. ext2_verify_disk_superblock() accepts zero group-size fields that get_ngroups() and get_itable_entry() later use as divisors during mounting. Exploitation requires an attacker-controlled image and a device using Zephyr's in-tree ext2 filesystem; affected Cortex-M targets raise a fatal UsageFault.

The record

CVE
CVE-2026-7007
Published
Jul 24, 2026
Updated
Jul 24, 2026
Vendor
Zephyr Project
Product
Zephyr RTOS
Classifications
CWE-369, T1499
Attack vector
physical
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 24, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 24, 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=3.5.0 <4.5.0

What conditions does exploitation require?

Attack vectorphysical
Required privilegesunauthenticated

What is affected?

Zephyr Project · Zephyr RTOSversion=3.5.0 <4.5.0

Published CVSS scores

4.6Zephyr ProjectCVSS:3.1/AV:P/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)
Vectorphysical
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-369Divide By Zero
T1499Endpoint Denial of Service

Public exploit references

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