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BareboxApplication · Pengutronix

CVE-2026-34960

MEDIUM · 6.5 CVSS v3.1 Published 2026-05-11
Fix available
A fix is available. Upgrade to 2026.04.0 or later.
See remediation →
70/100
Remediation priority · Elevated
No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
barebox prior to version 2026.04.0 contains an out-of-bounds read vulnerability in DHCP option parsing within the dhcp_message_type() function that fails to verify the options pointer remains within received packet bounds. An attacker on the same broadcast domain can send a crafted DHCP Offer or ACK packet without a proper 0xff end marker to cause the parser to read past valid packet data and potentially crash the system.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

barebox before 2026.04.0 has an out-of-bounds read vulnerability in the dhcp_message_type() function during DHCP option parsing. The function does not validate that the options pointer remains within the bounds of the received DHCP packet, allowing an attacker on the same broadcast domain to send a crafted DHCP Offer or ACK packet lacking the proper 0xff end marker, causing the parser to read past valid packet data and potentially crash the system.

MitigationUpgrade barebox to version 2026.04.0 or later, which contains bounds checking in DHCP option parsing. As a defensive measure, network segmentation can limit exposure to attackers on the same broadcast domain.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
BareboxApplication
Affected:< 2026.04.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify the installed barebox version
    Run 'barebox-version' or check the bootloader binary metadata at runtime, or inspect the barebox image file on the firmware partition for version strings like 'barebox-YYYY.MM'
    Affected if The version string shows a release earlier than 2026.04.0
  2. Confirm DHCP client functionality is enabled
    Check the barebox configuration or running config for DHCP client support - look for 'dhcp' command availability or CONFIG_NET_DHCP option in the built configuration
    Affected if DHCP client is compiled in and available on the system
  3. Determine if DHCP is actively used in the boot process
    Inspect boot scripts or environment (e.g., /env/boot or boot.scr) for 'dhcp' commands that fetch network configuration via DHCP at boot time
    Affected if Boot scripts contain dhcp commands that execute during boot
  4. Assess network exposure
    Review network configuration to determine if barebox operates on a shared broadcast network where untrusted DHCP servers could inject packets
    Affected if The system relies on DHCP on an untrusted or shared network segment

The system is affected if barebox version is earlier than 2026.04.0 AND the DHCP client feature is enabled and used to obtain network configuration at boot time.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 2026.04.0 or later
Fixed in 2026.04.0
Interim mitigation

Upgrade barebox to version 2026.04.0 or later, which contains bounds checking in DHCP option parsing. As a defensive measure, network segmentation can limit exposure to attackers on the same broadcast domain.

Recommended fix High confidence

barebox 2026.04.0

  1. Obtain barebox version 2026.04.0 or later from the official barebox repository (github.com/barebox/barebox)
  2. Build the new barebox version for your target platform following the standard build procedure
  3. Flash the compiled barebox image to your device using your platform's standard update mechanism
  4. Reboot the device to load the updated barebox
  5. Verify the installed barebox version is 2026.04.0 or later using the 'version' command

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Barebox Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing6.0 h
  • Review / QA2.0 h
14.0 hours of engineering $2,380
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,808.

Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-34960 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data