User thread can re-initialize an in-use `k_pipe`, corrupting kernel wait queues (`CONFIG_USERSPACE`)
Summary
| CVE | CVE-2026-10671 |
|---|---|
| State | PUBLISHED |
| Assigner | zephyr |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-07-14 15:16:55 UTC |
| Updated | 2026-07-14 19:16:50 UTC |
| Description | In Zephyr's kernel pipe implementation, the userspace syscall verifier z_vrfy_k_pipe_init() in kernel/pipe.c used K_SYSCALL_OBJ() (which requires the kernel object to already be initialized) instead of K_SYSCALL_OBJ_NEVER_INIT() (which rejects an already-initialized object). As a result, on CONFIG_USERSPACE builds an unprivileged user thread that has been granted access to a k_pipe object can invoke the k_pipe_init syscall to re-initialize a pipe that is already in use. z_impl_k_pipe_init() unconditionally resets the ring buffer, sets pipe->waiting to 0, and re-initializes both wait queues (z_waitq_init on pipe->data and pipe->space) without waking or accounting for threads currently blocked on the pipe. Any thread already pended in k_pipe_read()/k_pipe_write() is left orphaned: still marked pending with pended_on pointing at the cleared wait queue and with stale qnode_dlist links into the (now re-initialized) embedded list head. When such an orphaned waiter is later timed out or woken, the scheduler calls sys_dlist_remove() on its stale node, writing through dangling prev/next pointers into kernel wait-queue/scheduler structures, causing list corruption (an attacker-driven invalid kernel write), lost wakeups, indefinitely blocked threads, and silent data loss. The flaw lets a deprivileged user thread corrupt the state of a kernel object shared with other threads/partitions. The fix switches the verifier to K_SYSCALL_OBJ_NEVER_INIT(), matching the existing k_msgq_init verifier, so a user thread can no longer re-initialize a live pipe. The vulnerable code shipped in v4.1.0 and remained through v4.4.0. |
Risk And Classification
Primary CVSS: v3.1 7.1 HIGH from [email protected]
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
EPSS: 0.001030000 probability, percentile 0.011660000 (date 2026-07-15)
Problem Types: CWE-825 | CWE-825 memory-safety
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 7.1 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H |
| 3.1 | CNA | CVSS | 7.1 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H |
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
HighAvailability
HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Zephyrproject | Zephyr | affected 4.1.0 4.5.0 semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-p8w8-3x99-... | [email protected] | github.com | |
| github.com/zephyrproject-rtos/zephyr/commit/4424aa681e0b80e9cbd0ae27a987... | [email protected] | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.