{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-38262","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2025-04-16T04:51:23.997Z","datePublished":"2025-07-09T10:42:37.410Z","dateUpdated":"2026-08-05T12:00:50.359Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T12:00:50.359Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ntty: serial: uartlite: register uart driver in init\n\nWhen two instances of uart devices are probing, a concurrency race can\noccur. If one thread calls uart_register_driver function, which first\nallocates and assigns memory to 'uart_state' member of uart_driver\nstructure, the other instance can bypass uart driver registration and\ncall ulite_assign. This calls uart_add_one_port, which expects the uart\ndriver to be fully initialized. This leads to a kernel panic due to a\nnull pointer dereference:\n\n[    8.143581] BUG: kernel NULL pointer dereference, address: 00000000000002b8\n[    8.156982] #PF: supervisor write access in kernel mode\n[    8.156984] #PF: error_code(0x0002) - not-present page\n[    8.156986] PGD 0 P4D 0\n...\n[    8.180668] RIP: 0010:mutex_lock+0x19/0x30\n[    8.188624] Call Trace:\n[    8.188629]  ? __die_body.cold+0x1a/0x1f\n[    8.195260]  ? page_fault_oops+0x15c/0x290\n[    8.209183]  ? __irq_resolve_mapping+0x47/0x80\n[    8.209187]  ? exc_page_fault+0x64/0x140\n[    8.209190]  ? asm_exc_page_fault+0x22/0x30\n[    8.209196]  ? mutex_lock+0x19/0x30\n[    8.223116]  uart_add_one_port+0x60/0x440\n[    8.223122]  ? proc_tty_register_driver+0x43/0x50\n[    8.223126]  ? tty_register_driver+0x1ca/0x1e0\n[    8.246250]  ulite_probe+0x357/0x4b0 [uartlite]\n\nTo prevent it, move uart driver registration in to init function. This\nwill ensure that uart_driver is always registered when probe function\nis called."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The vulnerable window lives entirely in the uartlite platform-driver probe path, reachable only from local device/module instantiation (module load, deferred-probe worker, DT-overlay/FPGA-region or sysfs bind) on the affected host. No remote, adjacent, or physical-interface data reaches this code — the race is in driver registration, not in serial data handling.\nAC:L - Success requires the system to be in a specific state the attacker cannot create or influence — two uartlite instances probing simultaneously with one thread inside the few-microsecond window between `drv->state = kzalloc()` and `tty_port_init()`/`tty_register_driver()`. There is no way to widen, stall, or re-trigger that window from a local attacker's position, so it is a condition truly beyond attacker control.\nPR:L - Scored as a local unprivileged attacker present on an affected FPGA/embedded system when the concurrent probe occurs; the code itself performs no capability check. Deliberately forcing a probe (modprobe, sysfs bind, DT overlay) would need root, but the higher-severity assumption of a merely unprivileged local presence is used here.\nUI:N - The race fires during driver/device initialization driven by the kernel's own probe machinery; no victim action such as opening a device, mounting a filesystem, or loading a file is required.\nS:U - The corruption is confined to kernel data structures (`uart_driver.state`, `tty_port`, slab objects) within the same security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - This is not a bare NULL dereference — `uart_add_one_port()` reads through a half-built or already-`kfree()`d `drv->state`/`drv->tty_driver` (`drv->tty_driver->minor_start`, `state->uart_port`), giving reads of freed slab memory whose contents can be reallocated to other objects, so it is leverageable for kernel memory disclosure.\nI:H - In the double-registration interleaving the losing thread's error path `kfree()`s the shared `drv->state` array while the winner writes through it (`atomic_set(&state->refcount,1)`, `init_waitqueue_head()`, `state->uart_port = uport`, `tty_port_link_device()`), a use-after-free write that plants kernel pointers and performs list/mutex operations inside a freed, potentially reallocated slab object — memory corruption usable for control-flow hijacking.\nA:H - The documented and reproduced outcome is an immediate kernel panic (`BUG: kernel NULL pointer dereference` in `mutex_lock` from `uart_add_one_port`), and `BUG_ON(drv->state)` in the concurrent `uart_register_driver()` is a second crash path. On 5.4–6.12 the oops happens while the global `port_mutex` is held, permanently deadlocking all further serial-port and console registration even if the box survives the oops."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/tty/serial/uartlite.c"],"versions":[{"version":"238b8721a554a33a451a3f13bdb5be8fe5cfc927","lessThan":"5015eed450005bab6e5cb6810f7a62eab0434fc4","status":"affected","versionType":"git"},{"version":"238b8721a554a33a451a3f13bdb5be8fe5cfc927","lessThan":"9c905fdbba68a6d73d39a6b7de9b9f0d6c46df87","status":"affected","versionType":"git"},{"version":"238b8721a554a33a451a3f13bdb5be8fe5cfc927","lessThan":"6db06aaea07bb7c8e33a425cf7b98bf29ee6056e","status":"affected","versionType":"git"},{"version":"238b8721a554a33a451a3f13bdb5be8fe5cfc927","lessThan":"8e958d10dd0ce5ae674cce460db5c9ca3f25243b","status":"affected","versionType":"git"},{"version":"238b8721a554a33a451a3f13bdb5be8fe5cfc927","lessThan":"685d29f2c5057b32c7b1b46f2a7d303b926c8f72","status":"affected","versionType":"git"},{"version":"238b8721a554a33a451a3f13bdb5be8fe5cfc927","lessThan":"f5e4229d94792b40e750f30c92bcf7a3107c72ef","status":"affected","versionType":"git"},{"version":"238b8721a554a33a451a3f13bdb5be8fe5cfc927","lessThan":"6bd697b5fc39fd24e2aa418c7b7d14469f550a93","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/tty/serial/uartlite.c"],"versions":[{"version":"2.6.20","status":"affected"},{"version":"0","lessThan":"2.6.20","status":"unaffected","versionType":"semver"},{"version":"5.4.296","lessThanOrEqual":"5.4.*","status":"unaffected","versionType":"semver"},{"version":"5.15.187","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.143","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.96","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.36","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.15.5","lessThanOrEqual":"6.15.*","status":"unaffected","versionType":"semver"},{"version":"6.16","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.20","versionEndExcluding":"5.4.296"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.20","versionEndExcluding":"5.15.187"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.20","versionEndExcluding":"6.1.143"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.20","versionEndExcluding":"6.6.96"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.20","versionEndExcluding":"6.12.36"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.20","versionEndExcluding":"6.15.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.20","versionEndExcluding":"6.16"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/5015eed450005bab6e5cb6810f7a62eab0434fc4"},{"url":"https://git.kernel.org/stable/c/9c905fdbba68a6d73d39a6b7de9b9f0d6c46df87"},{"url":"https://git.kernel.org/stable/c/6db06aaea07bb7c8e33a425cf7b98bf29ee6056e"},{"url":"https://git.kernel.org/stable/c/8e958d10dd0ce5ae674cce460db5c9ca3f25243b"},{"url":"https://git.kernel.org/stable/c/685d29f2c5057b32c7b1b46f2a7d303b926c8f72"},{"url":"https://git.kernel.org/stable/c/f5e4229d94792b40e750f30c92bcf7a3107c72ef"},{"url":"https://git.kernel.org/stable/c/6bd697b5fc39fd24e2aa418c7b7d14469f550a93"}],"title":"tty: serial: uartlite: register uart driver in init","x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CVE Program Container","references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"}],"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2025-11-03T17:36:04.315Z"}}]}}