https://db.gcve.eu Contains only the most 10 recent entries. http://www.rssboard.org/rss-specification python-feedgen en Fri, 13 Nov 2026 23:40:07 +0000 https://db.gcve.eu/vuln/fkie_cve-2026-16662 <p>boot_save_boot_status() in boot/bootutil/src/boot_record.c reads the image&#39;s EXPECTED_HASH_TLV into a stack buffer image_hash[IMAGE_HASH_SIZE] that is never zero-initialised. The TLV handler validates only the upper bound (len &gt; sizeof(image_hash)) and then reads exactly len bytes, so a TLV shorter than IMAGE_HASH_SIZE leaves the tail of image_hash holding stale stack content. The subsequent copy into the boot record, memcpy(buf + offset, image_hash, sizeof(image_hash)), uses the fixed buffer size rather than len, so up to IMAGE_HASH_SIZE - 1 bytes of uninitialised bootloader stack are written into the measured-boot record.</p> <p>The defect is reachable only under MCUBOOT_MEASURED_BOOT, and only when the image reaching boot_save_boot_status() was not hash-validated on that boot. bootutil_img_validate() rejects a hash TLV whose length is not exactly sizeof(hash) (boot/bootutil/src/image_validate.c:345), and primary-slot validation is on by default (Zephyr&#39;s CONFIG_BOOT_VALIDATE_SLOT0 defaults to y), so in a default build the malformed image never reaches this code. The direct-XIP and RAM-load strategies in boot/bootutil/src/loader.c validate the selected slot unconditionally and are not affected. The short TLV survives only where the integrator has turned primary-slot validation off: the swap and overwrite loader built without MCUBOOT_VALIDATE_PRIMARY_SLOT, which checks only the image magic before calling boot_add_shared_data(), and the Zephyr single-slot loader (boot/zephyr/singl…</p> <p>boot_save_boot_status() in boot/bootutil/src/boot_record.c reads the image&#39;s EXPECTED_HASH_TLV into a stack buffer image_hash[IMAGE_HASH_SIZE] that is never zero-initialised. The TLV handler validates only the upper bound (len &gt; sizeof(image_hash)) and then reads exactly len bytes, so a TLV shorter than IMAGE_HASH_SIZE leaves the tail of image_hash holding stale stack content. The subsequent copy into the boot record, memcpy(buf + offset, image_hash, sizeof(image_hash)), uses the fixed buffer size rather than len, so up to IMAGE_HASH_SIZE - 1 bytes of uninitialised bootloader stack are written into the measured-boot record.</p> <p>The defect is reachable only under MCUBOOT_MEASURED_BOOT, and only when the image reaching boot_save_boot_status() was not hash-validated on that boot. bootutil_img_validate() rejects a hash TLV whose length is not exactly sizeof(hash) (boot/bootutil/src/image_validate.c:345), and primary-slot validation is on by default (Zephyr&#39;s CONFIG_BOOT_VALIDATE_SLOT0 defaults to y), so in a default build the malformed image never reaches this code. The direct-XIP and RAM-load strategies in boot/bootutil/src/loader.c validate the selected slot unconditionally and are not affected. The short TLV survives only where the integrator has turned primary-slot validation off: the swap and overwrite loader built without MCUBOOT_VALIDATE_PRIMARY_SLOT, which checks only the image magic before calling boot_add_shared_data(), and the Zephyr single-slot loader (boot/zephyr/singl…</p> https://db.gcve.eu/vuln/fkie_cve-2026-16662 https://db.gcve.eu/vuln/ghsa-wwg9-9xxp-r5fj <p>boot_save_boot_status() in boot/bootutil/src/boot_record.c reads the image&#39;s EXPECTED_HASH_TLV into a stack buffer image_hash[IMAGE_HASH_SIZE] that is never zero-initialised. The TLV handler validates only the upper bound (len &gt; sizeof(image_hash)) and then reads exactly len bytes, so a TLV shorter than IMAGE_HASH_SIZE leaves the tail of image_hash holding stale stack content. The subsequent copy into the boot record, memcpy(buf + offset, image_hash, sizeof(image_hash)), uses the fixed buffer size rather than len, so up to IMAGE_HASH_SIZE - 1 bytes of uninitialised bootloader stack are written into the measured-boot record.</p> <p>The defect is reachable only under MCUBOOT_MEASURED_BOOT, and only when the image reaching boot_save_boot_status() was not hash-validated on that boot. bootutil_img_validate() rejects a hash TLV whose length is not exactly sizeof(hash) (boot/bootutil/src/image_validate.c:345), and primary-slot validation is on by default (Zephyr&#39;s CONFIG_BOOT_VALIDATE_SLOT0 defaults to y), so in a default build the malformed image never reaches this code. The direct-XIP and RAM-load strategies in boot/bootutil/src/loader.c validate the selected slot unconditionally and are not affected. The short TLV survives only where the integrator has turned primary-slot validation off: the swap and overwrite loader built without MCUBOOT_VALIDATE_PRIMARY_SLOT, which checks only the image magic before calling boot_add_shared_data(), and the Zephyr single-slot loader (boot/zephyr/singl…</p> <p>boot_save_boot_status() in boot/bootutil/src/boot_record.c reads the image&#39;s EXPECTED_HASH_TLV into a stack buffer image_hash[IMAGE_HASH_SIZE] that is never zero-initialised. The TLV handler validates only the upper bound (len &gt; sizeof(image_hash)) and then reads exactly len bytes, so a TLV shorter than IMAGE_HASH_SIZE leaves the tail of image_hash holding stale stack content. The subsequent copy into the boot record, memcpy(buf + offset, image_hash, sizeof(image_hash)), uses the fixed buffer size rather than len, so up to IMAGE_HASH_SIZE - 1 bytes of uninitialised bootloader stack are written into the measured-boot record.</p> <p>The defect is reachable only under MCUBOOT_MEASURED_BOOT, and only when the image reaching boot_save_boot_status() was not hash-validated on that boot. bootutil_img_validate() rejects a hash TLV whose length is not exactly sizeof(hash) (boot/bootutil/src/image_validate.c:345), and primary-slot validation is on by default (Zephyr&#39;s CONFIG_BOOT_VALIDATE_SLOT0 defaults to y), so in a default build the malformed image never reaches this code. The direct-XIP and RAM-load strategies in boot/bootutil/src/loader.c validate the selected slot unconditionally and are not affected. The short TLV survives only where the integrator has turned primary-slot validation off: the swap and overwrite loader built without MCUBOOT_VALIDATE_PRIMARY_SLOT, which checks only the image magic before calling boot_add_shared_data(), and the Zephyr single-slot loader (boot/zephyr/singl…</p> https://db.gcve.eu/vuln/ghsa-wwg9-9xxp-r5fj