{"cve":"CVE-2026-46173","nvd":{"published":"2026-05-28T10:16:32.923","modified":"2026-10-19T20:18:36.167","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nexit: prevent preemption of oopsing TASK_DEAD task\n\nWhen an already-exiting task oopses, make_task_dead() currently calls\ndo_task_dead() with preemption enabled.  That is forbidden:\ndo_task_dead() calls __schedule(), which has a comment saying \"WARNING:\nmust be called with preemption disabled!\".\n\nIf an oopsing task is preempted in do_task_dead(), between becoming\nTASK_DEAD and entering the scheduler explicitly, bad things happen:\nfinish_task_switch() assumes that once the scheduler has switched away\nfrom a TASK_DEAD task, the task can never run again and its stack is no\nlonger needed; but that assumption apparently doesn't hold if the dead\ntask was preempted (the SM_PREEMPT case).\n\nThis means that the scheduler ends up repeatedly dropping references on\nthe dead task's stack, which can lead to use-after-free or double-free\nof the entire task stack; in other words, two tasks can end up running\non the same stack, resulting in various kinds of memory corruption.\n\n(This does not just affect \"recursively oopsing\" tasks; it is enough to\noops once during task exit, for example in a file_operations::release\nhandler)","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-787","CWE-416"],"references":["https://git.kernel.org/stable/c/3d6fb8a7690c23e3213c4b008f64d89a44b98737","https://git.kernel.org/stable/c/640b4c00fb0e2920327435f6176cbefc3c546165","https://git.kernel.org/stable/c/6f49f94f3b11fe8bff1bf2a054143789e76aaf17","https://git.kernel.org/stable/c/7b2800ba5f5f77a8ee7f4cbadb19cf1264597a34","https://git.kernel.org/stable/c/9756b3db5db6c2f5eccb32dddbd88eb4c54f575e"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-21T03:43:09.190223697+00:00"},"epss":{"cve":"CVE-2026-46173","score":0.00132,"percentile":0.02725,"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."]}