CVE-2026-127928

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Source

https://cve.org/CVERecord?id=CVE-2026-127928

Import Source

https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-127928.json

JSON Data

https://api.osv.dev/v1/vulns/CVE-2026-127928

Aliases

GHSA-hqmg-jwp9-8cf8

Published

2026-11-13T00:22:56Z

Modified

2026-11-13T13:10:12Z

Severity

2.0 (Low) CVSS_V3 - CVSS:3.1/AV:P/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N CVSS Calculator

Summary

AES image key left on the stack after serial-recovery encrypted-image handling in MCUboot

Details

In MCUboot's serial-recovery encrypted-image support (boot/boot_serial/src/boot_serial_encryption.c), decrypt_image_inplace() and boot_image_validate_encrypted() each keep a stack-local struct boot_status. boot_enc_load() writes the plaintext per-image AES key into its enckey[] field. Neither function cleared this structure before returning. In addition, a decrypt failure inside the per-sector loop of decrypt_image_inplace() returned early and skipped the total_out: cleanup, which left the expanded AES key context (enc_data) on the stack as well. The error paths of boot_image_validate_encrypted() similarly skipped boot_enc_zeroize().

The affected code is built when encrypted images (MCUBOOT_ENC_IMAGES, Zephyr CONFIG_BOOT_ENCRYPT_IMAGE) are combined with serial recovery. It runs when an encrypted image is uploaded to the primary slot over the recovery protocol, and when the image list or state is queried while an encrypted image is in the secondary slot. After these functions return, the image's AES content key remains in dead stack memory. An attacker who can later read device RAM, for example through a debug port or retained RAM, can recover it.

This weakens the confidentiality of image-encryption keys within the bootloader trust boundary. A recovered key exposes the plaintext of the encrypted firmware image it protects. The device's long-term private decryption key is not exposed. No remote or recovery-protocol channel that returns this memory is known, so exploitation requires a separate memory-read capability.

Database specific

{
    "cna_assigner": "zephyr",
    "cwe_ids": [
        "CWE-226"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/127xxx/CVE-2026-127928.json"
}

References

Affected packages

Git / github.com/mcu-tools/mcuboot

Affected ranges

Type

GIT

Repo

https://github.com/mcu-tools/mcuboot

Events

Introduced

dc0ca086f98432b39a482c3ddcf214b9a44c2152

Fixed

725d63c9d5bc1bb572d802e7a768daf504186daf

Fixed

411949f830724617fbc08b9b32f0a45ba0c80baf

Database specific

Show details

{
    "extracted_events": [
        {
            "range": [
                {
                    "introduced": "1.9.0"
                },
                {
                    "fixed": "2.5.0"
                }
            ],
            "source": "AFFECTED_FIELD",
            "strategy": "StandardRange"
        },
        {
            "range": [
                {
                    "fixed": "411949f830724617fbc08b9b32f0a45ba0c80baf"
                }
            ],
            "source": "REFERENCES_COMMIT"
        }
    ]
}

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-127928.json"

vanir_signatures

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        "id": "CVE-2026-127928-12edb89a",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/mcu-tools/mcuboot/commit/411949f830724617fbc08b9b32f0a45ba0c80baf",
        "target": {
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]

vanir_signatures_modified

"2026-11-13T13:10:12Z"