CVE-2026-33243
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.
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
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 High
CVSS: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 High
CVSS: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 High
CVSS: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 High
CVSS: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 High
CVSS: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 High
CVSS: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 High
CVSS: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
| Package | Affected | Fixed |
|---|---|---|
uboot-toolsopenEuler:24.03-LTS-SP3 |
before 2024.01-3.oe2403sp3 | 2024.01-3.oe2403sp3 |
uboot-toolsopenEuler:20.03-LTS-SP4 |
before 2020.07-10.oe2003sp4 | 2020.07-10.oe2003sp4 |
uboot-toolsopenEuler:22.03-LTS-SP4 |
before 2021.10-11.oe2203sp4 | 2021.10-11.oe2203sp4 |
uboot-toolsopenEuler:24.03-LTS |
before 2024.01-3.oe2403sp2 | 2024.01-3.oe2403sp2 |
uboot-toolsopenEuler:24.03-LTS-SP1 |
before 2024.01-3.oe2403sp1 | 2024.01-3.oe2403sp1 |
uboot-toolsopenEuler:24.03-LTS-SP2 |
before 2024.01-3.oe2403sp2 | 2024.01-3.oe2403sp2 |
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | ||
| affected | ||
| first indexed | CVE 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
github.com/barebox/barebox/security/advisories/GHSA-3fvj-q26p-j6h4
github.com/barebox/barebox/commit/aca01795056d51060cb096f9a1ea309361743e05
github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33243.json
nvd.nist.gov/vuln/detail/CVE-2026-33243
github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46728.json
nvd.nist.gov/vuln/detail/CVE-2026-46728
github.com/u-boot/u-boot/commit/2092322b31cc8b1f8c9e2e238d1043ae0637b241
security-tracker.debian.org/tracker/CVE-2026-33243
openeuler.org/zh/security/security-bulletins/detail?id=openEuler-SA-2026-1834