{"id":"CVE-2026-89500","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-89500","summary":"ring-buffer: Make cpu_buffer::free_page a buffer_data_read_page","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nring-buffer: Make cpu_buffer::free_page a buffer_data_read_page\n\nDiscarding a cached reader page after a concurrent ring buffer resize\nuses the new global subbuf_order for the free_pages() call. This\nmismatched order may crashes the kernel or leaks memory because the cached\npage was allocated under the old size.\n\nSave the actual free_page order alongside the page address to ensure we\nalways refer to the correct value and do not rely on the potentially\nstalled cpu_buffer->subbuf_order value. The simplest is to make\nfree_page a buffer_data_read_page which already covers exactly what we\nneed: a page address and a page order.","published":"2026-09-11T19:43:49.392Z","modified":"2026-09-14T03:46:10.347332147Z","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":"WEB","url":"https://git.kernel.org/stable/c/7a1fb95de5404134f8758c1295ce88986bdf117c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a1dabe68fb53730bc0be60c5dbfd3f4c560084e7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d787d509bdf6c88c85e095247daf7456cb7fb772"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89500.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89500"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-14T03:46:10.347332147Z"}}