{"id":"CVE-2026-90046","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-90046","summary":"mm/page_alloc: don't spin_trylock() in NMI on UP","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/page_alloc: don't spin_trylock() in NMI on UP\n\nPatch series \"mm/page_alloc: fixes for free_pages_nolock() on RT/UP\".\n\nPre-existing bugs found by Sashiko during review of this other series:\nhttps://lore.kernel.org/all/20260703-alloc-trylock-v5-0-c87b714e19d3@google.com/\n\nI have not reproduced these bugs, and I suspect there is no real-world\nuser that is affected by them.\n\n\nThis patch (of 2):\n\nAs noted in can_spin_trylock(), using this is unsafe in this context. \ncommit 620b46ed6ae17 (\"mm/page_alloc: return NULL early from\nalloc_frozen_pages_nolock() in NMI on UP\") fixed this on the alloc side\nbut missed the free side.\n\nImpact: If BPF programs using these features in NMI (probably tracing) are\npresent on non-SMP builds this might crash the kernel and is probably\nexploitable by local attackers for privilege escalation.","published":"2026-09-16T10:33:43.156Z","modified":"2026-09-17T03:47:20.396575622Z","cvss":{"score":7.8,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"6.18.51"}],"fix":null,"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/06c76d3c389ff504052f64b1acee44651bd847fa"},{"type":"WEB","url":"https://git.kernel.org/stable/c/3105ae628fb785d48b49256468be4f21a7b3cfc0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/68a069b407303e71db371df85036101e8ff59280"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90046.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-90046"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-17T03:47:20.396575622Z"}}