{"id":"CVE-2026-98788","revision":"29bdee29577045efb0ecbebd43127b63","records":[{"revision":"29bdee29577045efb0ecbebd43127b63","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-98788","aliases":[],"title":"futex: Fix private hash use-after-free on resize","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nfutex: Fix private hash use-after-free on resize\n\npoll_state_synchronize_rcu(mm->futex.phash.batches) is used by\nfutex_ref_drop() to check that a grace period has passed since the\ncurrent hash was published. This relies on batches referencing a grace\nperiod which started after the hash pointer was assigned.\n\n__futex_pivot_hash() sets mmph->batches before it replaces mmph->hash:\n\n    scoped_guard(rcu) {\n            mmph->batches = get_state_synchronize_rcu();\n            rcu_assign_pointer(mmph->hash, new);\n    }\n\nThe scoped_guard(rcu) doesn't stop new grace periods from starting, and\nif one starts between those two assignments, futex_ref_drop() can move\nforward while a reader still holds a pointer to the old hash.\n\nFix things by setting mmph->batches after assigning mmph->hash.  The\nscoped_guard(rcu) isn't needed, so let's drop that as well.","state":0,"publishedAt":"2026-10-18T15:48:24.833+00:00","modifiedAt":"2026-10-19T09:25:41.209+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"kernel/futex/core.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"56180dd20c19e5b0fa34822997a9ac66b517e7b3\",\n                            \"lessThan\": \"5d5dc18b3a9ac011619b7d3af4514bf9e9b6a6af\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"56180dd20c19e5b0fa34822997a9ac66b517e7b3\",\n                            \"lessThan\": \"f35e3b5784221654f9cdbd6222275a7fa203f6c3\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"kernel/futex/core.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"6.17\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"6.17\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.10\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/5d5dc18b3a9ac011619b7d3af4514bf9e9b6a6af","https://git.kernel.org/stable/c/f35e3b5784221654f9cdbd6222275a7fa203f6c3"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98788","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-98788","identifiers":["CVE-2026-98788"]},"retained":false,"historicalAffected":[]}],"coverage":[]}