{"id":"CVE-2026-10674","aliases":["EUVD-2026-46444","GHSA-mw68-r353-m3vf"],"status":"published","title":"DoS (hard fault) in NXP LPUART driver: unsupported runtime UART config leaves clocks disabled","description":"The NXP LPUART serial driver (drivers/serial/uart_mcux_lpuart.c), when CONFIG_UART_USE_RUNTIME_CONFIGURE is enabled, called LPUART_Deinit() at the start of mcux_lpuart_configure(), which disables the LPUART peripheral clocks. The requested configuration is validated only afterwards (in mcux_lpuart_configure_basic), and unsupported parity/data-bit/stop-bit/flow-control values return -ENOTSUP before the clock is re-enabled.\n\nAs a result, a uart_configure() request with an unsupported configuration left the LPUART in a clock-disabled state; any subsequent access to LPUART registers (poll_out/poll_in, interrupt handling, or a later reconfigure) faults on the gated peripheral and escalates to a hard fault, crashing the system.\n\nuart_configure() is a Zephyr syscall whose verifier (z_vrfy_uart_configure) only checks that cfg is readable user memory and forwards the caller-supplied configuration unchanged, so an unprivileged userspace thread with access to an LPUART device can deterministically trigger the fault, a persistent system-wide denial of service.\n\nIntroduced in v2.5.0 and present in all subsequent releases until this fix, which removes the LPUART_Deinit() call and instead only disables the transmitter/receiver, leaving the clock running.","severity":{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00143,"percentile":0.03641,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-617"],"published":"2026-07-21T21:30:53Z","modified":"2026-10-28T11:03:52Z","products":[{"vendor":"zephyrproject","product":"zephyr"},{"vendor":"zephyrproject-rtos","product":"zephyr"}],"references":[{"url":"https://github.com/zephyrproject-rtos/zephyr/commit/f56935c46fdf6559a20ad8484b29896ecac5808f","tags":["patch","Patch","fix"]},{"url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-mw68-r353-m3vf","tags":["Patch","Vendor Advisory","advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/10xxx/CVE-2026-10674.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-10674","tags":["advisory"]},{"url":"https://github.com/zephyrproject-rtos/zephyr","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-10674","title":"DoS (hard fault) in NXP LPUART driver: unsupported runtime UART config leaves clocks disabled","description":"The NXP LPUART serial driver (drivers/serial/uart_mcux_lpuart.c), when CONFIG_UART_USE_RUNTIME_CONFIGURE is enabled, called LPUART_Deinit() at the start of mcux_lpuart_configure(), which disables the LPUART peripheral clocks. The requested configuration is validated only afterwards (in mcux_lpuart_configure_basic), and unsupported parity/data-bit/stop-bit/flow-control values return -ENOTSUP before the clock is re-enabled.\n\nAs a result, a uart_configure() request with an unsupported configuration left the LPUART in a clock-disabled state; any subsequent access to LPUART registers (poll_out/poll_in, interrupt handling, or a later reconfigure) faults on the gated peripheral and escalates to a hard fault, crashing the system.\n\nuart_configure() is a Zephyr syscall whose verifier (z_vrfy_uart_configure) only checks that cfg is readable user memory and forwards the caller-supplied configuration unchanged, so an unprivileged userspace thread with access to an LPUART device can deterministically trigger the fault, a persistent system-wide denial of service.\n\nIntroduced in v2.5.0 and present in all subsequent releases until this fix, which removes the LPUART_Deinit() call and instead only disables the transmitter/receiver, leaving the clock running.","status":"published","published":"2026-07-21T21:30:53.643Z","modified":"2026-10-15T22:10:16.575Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna"}],"cwes":["CWE-617"],"updated_at":"2026-11-02T13:40:12.486331Z"}],"euvd":[{"id":"EUVD-2026-46444","description":"The NXP LPUART serial driver (drivers/serial/uart_mcux_lpuart.c), when CONFIG_UART_USE_RUNTIME_CONFIGURE is enabled, called LPUART_Deinit() at the start of mcux_lpuart_configure(), which disables the LPUART peripheral clocks. The requested configuration is validated only afterwards (in mcux_lpuart_configure_basic), and unsupported parity/data-bit/stop-bit/flow-control values return -ENOTSUP before the clock is re-enabled.\n\nAs a result, a uart_configure() request with an unsupported configuration left the LPUART in a clock-disabled state; any subsequent access to LPUART registers (poll_out/poll_in, interrupt handling, or a later reconfigure) faults on the gated peripheral and escalates to a hard fault, crashing the system.\n\nuart_configure() is a Zephyr syscall whose verifier (z_vrfy_uart_configure) only checks that cfg is readable user memory and forwards the caller-supplied configuration unchanged, so an unprivileged userspace thread with access to an LPUART device can deterministically trigger the fault, a persistent system-wide denial of service.\n\nIntroduced in v2.5.0 and present in all subsequent releases until this fix, which removes the LPUART_Deinit() call and instead only disables the transmitter/receiver, leaving the clock running.","status":"published","published":"2026-07-21T21:30:53Z","modified":"2026-10-15T22:10:16Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T17:00:07.251605Z"}],"nvd":[{"id":"CVE-2026-10674","description":"The NXP LPUART serial driver (drivers/serial/uart_mcux_lpuart.c), when CONFIG_UART_USE_RUNTIME_CONFIGURE is enabled, called LPUART_Deinit() at the start of mcux_lpuart_configure(), which disables the LPUART peripheral clocks. The requested configuration is validated only afterwards (in mcux_lpuart_configure_basic), and unsupported parity/data-bit/stop-bit/flow-control values return -ENOTSUP before the clock is re-enabled.\n\nAs a result, a uart_configure() request with an unsupported configuration left the LPUART in a clock-disabled state; any subsequent access to LPUART registers (poll_out/poll_in, interrupt handling, or a later reconfigure) faults on the gated peripheral and escalates to a hard fault, crashing the system.\n\nuart_configure() is a Zephyr syscall whose verifier (z_vrfy_uart_configure) only checks that cfg is readable user memory and forwards the caller-supplied configuration unchanged, so an unprivileged userspace thread with access to an LPUART device can deterministically trigger the fault, a persistent system-wide denial of service.\n\nIntroduced in v2.5.0 and present in all subsequent releases until this fix, which removes the LPUART_Deinit() call and instead only disables the transmitter/receiver, leaving the clock running.","status":"published","published":"2026-07-21T22:16:58.74Z","modified":"2026-10-24T19:10:00.127Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"secondary"}],"cwes":["CWE-617"],"updated_at":"2026-11-02T14:12:31.394335Z"}],"osv":[{"id":"CVE-2026-10674","title":"DoS (hard fault) in NXP LPUART driver: unsupported runtime UART config leaves clocks disabled","description":"The NXP LPUART serial driver (drivers/serial/uart_mcux_lpuart.c), when CONFIG_UART_USE_RUNTIME_CONFIGURE is enabled, called LPUART_Deinit() at the start of mcux_lpuart_configure(), which disables the LPUART peripheral clocks. The requested configuration is validated only afterwards (in mcux_lpuart_configure_basic), and unsupported parity/data-bit/stop-bit/flow-control values return -ENOTSUP before the clock is re-enabled.\n\nAs a result, a uart_configure() request with an unsupported configuration left the LPUART in a clock-disabled state; any subsequent access to LPUART registers (poll_out/poll_in, interrupt handling, or a later reconfigure) faults on the gated peripheral and escalates to a hard fault, crashing the system.\n\nuart_configure() is a Zephyr syscall whose verifier (z_vrfy_uart_configure) only checks that cfg is readable user memory and forwards the caller-supplied configuration unchanged, so an unprivileged userspace thread with access to an LPUART device can deterministically trigger the fault, a persistent system-wide denial of service.\n\nIntroduced in v2.5.0 and present in all subsequent releases until this fix, which removes the LPUART_Deinit() call and instead only disables the transmitter/receiver, leaving the clock running.","status":"published","published":"2026-07-21T21:30:53.643Z","modified":"2026-10-28T11:03:52.534711899Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-617"],"updated_at":"2026-11-02T15:44:54.933106Z"}]}}
