{"cve":"CVE-2026-10677","nvd":{"published":"2026-07-21T22:16:59.923","modified":"2026-10-24T19:10:00.127","status":"Analyzed","description":"The CONFIG_USERSPACE syscall verifier z_vrfy_k_poll() in kernel/poll.c allocates a kernel-side copy of the user-supplied k_poll_event[] via z_thread_malloc() and then validates each event's object handle. Before this fix, validation used K_OOPS(K_SYSCALL_OBJ(...)) inline inside the loop, which kills the calling thread without freeing events_copy.\n\nA user thread can pass num_events >= 1 with a forged object handle to leak the allocation; because newly spawned user threads inherit the parent's resource_pool (kernel/thread.c), an attacker spawns sacrificial threads to repeat the leak until the shared kernel heap is exhausted. Once depleted, legitimate kernel allocations from that pool (k_queue alloc nodes, k_msgq buffers, future k_poll calls, etc.) fail, causing a system-level denial of service.\n\nThe fix replaces each inline K_OOPS with a conditional goto oops_free so the buffer is freed before the thread is killed. Affects Zephyr releases from v1.12.0 (when k_poll was first exposed to user mode) through v4.4.1.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H","score":6.5},"cwes":["CWE-401"],"references":["https://github.com/zephyrproject-rtos/zephyr/commit/8dc7a37bc75402a0a3329397887f32f5fb4da3ad","https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-r3cc-8wcr-xfj9"],"products":["zephyrproject:zephyr"],"source":"nvd","synced_at":"2026-10-25T17:50:08.599881581+00:00"},"epss":{"cve":"CVE-2026-10677","score":0.00143,"percentile":0.03565,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}