{"cve":"CVE-2023-53419","nvd":{"published":"2025-09-18T16:15:45.650","modified":"2026-06-17T06:45:16.690","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nrcu: Protect rcu_print_task_exp_stall() ->exp_tasks access\n\nFor kernels built with CONFIG_PREEMPT_RCU=y, the following scenario can\nresult in a NULL-pointer dereference:\n\n           CPU1                                           CPU2\nrcu_preempt_deferred_qs_irqrestore                rcu_print_task_exp_stall\n  if (special.b.blocked)                            READ_ONCE(rnp->exp_tasks) != NULL\n    raw_spin_lock_rcu_node\n    np = rcu_next_node_entry(t, rnp)\n    if (&t->rcu_node_entry == rnp->exp_tasks)\n      WRITE_ONCE(rnp->exp_tasks, np)\n      ....\n      raw_spin_unlock_irqrestore_rcu_node\n                                                    raw_spin_lock_irqsave_rcu_node\n                                                    t = list_entry(rnp->exp_tasks->prev,\n                                                        struct task_struct, rcu_node_entry)\n                                                    (if rnp->exp_tasks is NULL, this\n                                                       will dereference a NULL pointer)\n\nThe problem is that CPU2 accesses the rcu_node structure's->exp_tasks\nfield without holding the rcu_node structure's ->lock and CPU2 did\nnot observe CPU1's change to rcu_node structure's ->exp_tasks in time.\nTherefore, if CPU1 sets rcu_node structure's->exp_tasks pointer to NULL,\nthen CPU2 might dereference that NULL pointer.\n\nThis commit therefore holds the rcu_node structure's ->lock while\naccessing that structure's->exp_tasks field.\n\n[ paulmck: Apply Frederic Weisbecker feedback. ]","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-476"],"references":["https://git.kernel.org/stable/c/2bc0ae94ef1f9ed322d8ee439de3239ea3632ab2","https://git.kernel.org/stable/c/3c1566bca3f8349f12b75d0a2d5e4a20ad6262ec","https://git.kernel.org/stable/c/a7d21b8585894e6fff973f6ddae42f02b13f600f","https://git.kernel.org/stable/c/d0a8c0e31a09ec1efd53079083e2a677956b4d91","https://git.kernel.org/stable/c/e30a55e98ae6c44253d8b129efefd5da5bc6e3bc"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:10:08.713834912+00:00"},"epss":{"cve":"CVE-2023-53419","score":0.00159,"percentile":0.05034,"date":"2026-11-01"},"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."]}