{"id":"CVE-2026-89965","revision":"972f956344654466835a7a380f0e9808","records":[{"revision":"972f956344654466835a7a380f0e9808","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-89965","aliases":[],"title":"nvdimm/btt: reject an arena whose nfree is below the lane count","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnvdimm/btt: reject an arena whose nfree is below the lane count\n\nThe BTT info block's nfree field, the number of reserve free blocks, is\nread from the medium without validation.  btt_freelist_init() and\nbtt_rtt_init() size the per-lane freelist[] and rtt[] arrays by nfree,\nbut the I/O path indexes them by the lane from nd_region_acquire_lane(),\nwhich is bounded by nd_region->num_lanes (ND_MAX_LANES), not by nfree.\nA crafted or foreign arena whose nfree is below the lane count makes\nfreelist[lane]/rtt[lane] run past the allocation: an out-of-bounds write.\n\nbtt.rst documents the nlanes = min(nfree, num_cpus) invariant, which the\ncode does not currently honor: num_lanes is ND_MAX_LANES regardless of\nnfree.  Reject an arena whose nfree is below num_lanes at discovery,\nbefore the per-lane arrays are allocated, enforcing that invariant.","state":0,"publishedAt":"2026-09-16T10:32:46.769+00:00","modifiedAt":"2026-10-19T08:55:38.886+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                        \"drivers/nvdimm/btt.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"5212e11fde4d40fa627668b4f2222d20db488f71\",\n                            \"lessThan\": \"eb491343d2d1784121ad9af91c25b338c28913c3\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"5212e11fde4d40fa627668b4f2222d20db488f71\",\n                            \"lessThan\": \"59d5cd1f42b4bab3609512c3cb3d3540d3d21da7\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"5212e11fde4d40fa627668b4f2222d20db488f71\",\n                            \"lessThan\": \"f6c5313aae794ecca8f762c1a3493de5c266f120\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"5212e11fde4d40fa627668b4f2222d20db488f71\",\n                            \"lessThan\": \"f9bf05c63b77d000e9c01f3e47af36973887d350\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"5212e11fde4d40fa627668b4f2222d20db488f71\",\n                            \"lessThan\": \"6f79d1a5f2611a3d36e9312be5425cd9cb397c51\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"5212e11fde4d40fa627668b4f2222d20db488f71\",\n                            \"lessThan\": \"6b1faf1f099f7060b5f1f2f0d024132581f1726e\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"5212e11fde4d40fa627668b4f2222d20db488f71\",\n                            \"lessThan\": \"9dfa11cef4750b67591307f2c62e47a23d60e4b7\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"5212e11fde4d40fa627668b4f2222d20db488f71\",\n                            \"lessThan\": \"6a1f2e5ed9267ca19187038ac635393c165213ac\",\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                        \"drivers/nvdimm/btt.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"4.2\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"4.2\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.270\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.221\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.188\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.157\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.110\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.51\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.5\",\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":[{"system":"CVSS 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,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/eb491343d2d1784121ad9af91c25b338c28913c3","https://git.kernel.org/stable/c/59d5cd1f42b4bab3609512c3cb3d3540d3d21da7","https://git.kernel.org/stable/c/f6c5313aae794ecca8f762c1a3493de5c266f120","https://git.kernel.org/stable/c/f9bf05c63b77d000e9c01f3e47af36973887d350","https://git.kernel.org/stable/c/6f79d1a5f2611a3d36e9312be5425cd9cb397c51","https://git.kernel.org/stable/c/6b1faf1f099f7060b5f1f2f0d024132581f1726e","https://git.kernel.org/stable/c/9dfa11cef4750b67591307f2c62e47a23d60e4b7","https://git.kernel.org/stable/c/6a1f2e5ed9267ca19187038ac635393c165213ac"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-89965","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-89965","identifiers":["CVE-2026-89965"]},"retained":false,"historicalAffected":[]}],"coverage":[]}