Every CVE Search/ Get API key

CVE-2026-33243

barebox: FIT Signature Verification Bypass Vulnerability

8.3 HighFix available

barebox is a bootloader. In barebox from version 2016.03.0 to before version 2026.03.1 (and the corresponding backport to 2025.09.3), an attacker could exploit a FIT signature verification vulnerability to trick the bootloader into booting different images than those that were verified as part of a signed configuration. mkimage(1) sets the hashed-nodes property of the FIT signature node to list which nodes of the FIT were hashed as part of the signing process as these will need to be verified later on by the bootloader. However, hashed-nodes itself is not part of the hash and could therefore be modified to allow booting different images than those that have been verified. This issue has been patched in barebox versions 2026.03.1 and backported to 2025.09.3.

Attack profile

How easy it is to exploit

Attack vector
Local
Complexity
Low
Privileges needed
High
User interaction
None

What an attacker can affect

Confidentiality
High
Integrity
High
Availability
High

Exploit likelihood

0.11%Up 0.1 points since Mar 21, 2026
90%50%10%1%

What each source reports

CVE List Score used 8.3

barebox: FIT Signature Verification Bypass Vulnerability

barebox is a bootloader. In barebox from version 2016.03.0 to before version 2026.03.1 (and the corresponding backport to 2025.09.3), an attacker could exploit a FIT signature verification vulnerability to trick the bootloader into booting different images than those that were verified as part of a signed configuration. mkimage(1) sets the hashed-nodes property of the FIT signature node to list which nodes of the FIT were hashed as part of the signing process as these will need to be verified later on by the bootloader. However, hashed-nodes itself is not part of the hash and could therefore be modified to allow booting different images than those that have been verified. This issue has been patched in barebox versions 2026.03.1 and backported to 2025.09.3.

Record
CVE-2026-33243
CVSS 3.1
8.3 HighCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Weakness
CWE-345
Updated
2026-11-02
EUVDEUVD-2026-13893 8.3

barebox is a bootloader. In barebox from version 2016.03.0 to before version 2026.03.1 (and the corresponding backport to 2025.09.3), an attacker could exploit a FIT signature verification vulnerability to trick the bootloader into booting different images than those that were verified as part of a signed configuration. mkimage(1) sets the hashed-nodes property of the FIT signature node to list which nodes of the FIT were hashed as part of the signing process as these will need to be verified later on by the bootloader. However, hashed-nodes itself is not part of the hash and could therefore be modified to allow booting different images than those that have been verified. This issue has been patched in barebox versions 2026.03.1 and backported to 2025.09.3.

Record
EUVD-2026-13893
CVSS 3.1
8.3 HighCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Updated
2026-11-02
NVD 8.2

barebox is a bootloader. In barebox from version 2016.03.0 to before version 2026.03.1 (and the corresponding backport to 2025.09.3), an attacker could exploit a FIT signature verification vulnerability to trick the bootloader into booting different images than those that were verified as part of a signed configuration. mkimage(1) sets the hashed-nodes property of the FIT signature node to list which nodes of the FIT were hashed as part of the signing process as these will need to be verified later on by the bootloader. However, hashed-nodes itself is not part of the hash and could therefore be modified to allow booting different images than those that have been verified. This issue has been patched in barebox versions 2026.03.1 and backported to 2025.09.3.

Record
CVE-2026-33243
CVSS 3.1
8.2 HighCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Weakness
CWE-345
Updated
2026-11-02
OSV 8.2

barebox: FIT Signature Verification Bypass Vulnerability

barebox is a bootloader. In barebox from version 2016.03.0 to before version 2026.03.1 (and the corresponding backport to 2025.09.3), an attacker could exploit a FIT signature verification vulnerability to trick the bootloader into booting different images than those that were verified as part of a signed configuration. mkimage(1) sets the hashed-nodes property of the FIT signature node to list which nodes of the FIT were hashed as part of the signing process as these will need to be verified later on by the bootloader. However, hashed-nodes itself is not part of the hash and could therefore be modified to allow booting different images than those that have been verified. This issue has been patched in barebox versions 2026.03.1 and backported to 2025.09.3.

Record
CVE-2026-33243
CVSS 3.1
8.2 HighCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Weakness
CWE-345
Updated
2026-11-02
OSVCVE-2026-46728 8.2

Das U-Boot before 2026.04 allows FIT (Flat Image Tree) signature verification bypass because hashed-nodes is omitted from a hash.

Record
CVE-2026-46728
CVSS 3.1
8.2 HighCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Weakness
CWE-346
Updated
2026-11-02
OSVDEBIAN-CVE-2026-33243 8.2

barebox is a bootloader. In barebox from version 2016.03.0 to before version 2026.03.1 (and the corresponding backport to 2025.09.3), an attacker could exploit a FIT signature verification vulnerability to trick the bootloader into booting different images than those that were verified as part of a signed configuration. mkimage(1) sets the hashed-nodes property of the FIT signature node to list which nodes of the FIT were hashed as part of the signing process as these will need to be verified later on by the bootloader. However, hashed-nodes itself is not part of the hash and could therefore be modified to allow booting different images than those that have been verified. This issue has been patched in barebox versions 2026.03.1 and backported to 2025.09.3.

Record
DEBIAN-CVE-2026-33243
CVSS 3.1
8.2 HighCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Updated
2026-11-02
OSVOESA-2026-1834 8.2

uboot-tools security update

This package includes the mkimage program, which allows generation of U-Boot images in various formats, and the fw_printenv and fw_setenv programs to read and modify U-Boot's environment.

Security Fix(es):

barebox is a bootloader. In barebox from version 2016.03.0 to before version 2026.03.1 (and the corresponding backport to 2025.09.3), an attacker could exploit a FIT signature verification vulnerability to trick the bootloader into booting different images than those that were verified as part of a signed configuration. mkimage(1) sets the hashed-nodes property of the FIT signature node to list which nodes of the FIT were hashed as part of the signing process as these will need to be verified later on by the bootloader. However, hashed-nodes itself is not part of the hash and could therefore be modified to allow booting different images than those that have been verified. This issue has been patched in barebox versions 2026.03.1 and backported to 2025.09.3.(CVE-2026-33243)

Record
OESA-2026-1834
CVSS 3.1
8.2 HighCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Updated
2026-11-02

Affected products

Affected packages

Affected packages
PackageAffectedFixed
uboot-tools
openEuler:24.03-LTS-SP3
before 2024.01-3.oe2403sp3
2024.01-3.oe2403sp3
uboot-tools
openEuler:20.03-LTS-SP4
before 2020.07-10.oe2003sp4
2020.07-10.oe2003sp4
uboot-tools
openEuler:22.03-LTS-SP4
before 2021.10-11.oe2203sp4
2021.10-11.oe2203sp4
uboot-tools
openEuler:24.03-LTS
before 2024.01-3.oe2403sp2
2024.01-3.oe2403sp2
uboot-tools
openEuler:24.03-LTS-SP1
before 2024.01-3.oe2403sp1
2024.01-3.oe2403sp1
uboot-tools
openEuler:24.03-LTS-SP2
before 2024.01-3.oe2403sp2
2024.01-3.oe2403sp2

History

History
RecordedChangedSources
facts
affected
first indexedCVE List, EUVD, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2026-33243 is a high vulnerability (CVSS 8.3) in Barebox, published March 20, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.11%, the 1st percentile. Fixed in uboot-tools 2024.01-3.oe2403sp3.

References

MoveEnter Open