{"id":"CVE-2026-72191","revision":"aad92a2044774ef7bc5a56bbb551ad6b","records":[{"revision":"aad92a2044774ef7bc5a56bbb551ad6b","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-72191","aliases":[],"title":"ntfs3: validate split-point offset in indx_insert_into_buffer","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nntfs3: validate split-point offset in indx_insert_into_buffer\n\nindx_insert_into_buffer() computes\n\n    used = used1 - to_copy - sp_size;\n    memmove(de_t, Add2Ptr(sp, sp_size), used - le32_to_cpu(hdr1->de_off));\n\nwhere sp and sp_size come from hdr_find_split().  hdr_find_split()\nwalks entries by le16_to_cpu(e->size) without validating that each\nstep stays within hdr->used or that the size field is at least\nsizeof(struct NTFS_DE).  index_hdr_check(), the on-load gatekeeper,\nonly validates header-level fields (used, total, de_off) and does\nnot walk per-entry sizes.\n\nA crafted NTFS image whose leaf INDEX_HDR reports used == total but\ncontains one interior NTFS_DE with size = 0xFFF0 therefore passes\nvalidation, descends to indx_insert_into_buffer() through the\nntfs_create() -> indx_insert_entry() path, and makes hdr_find_split()\nreturn an sp whose sp_size (0xFFF0) greatly exceeds the remaining\nbytes in the buffer.  The u32 subtraction underflows and the memmove\ncount becomes a near-4-GiB value, producing an out-of-bounds kernel\nwrite that corrupts adjacent allocations and panics the kernel.\n\nReproduced on 7.0.0-rc7 with UML + KASAN via a crafted image and a\nsingle 'touch' inside the mounted directory; crash site resolves to\nfs/ntfs3/index.c at the memmove.  Trigger requires only local mount\nof an attacker-supplied filesystem image (USB, loopback, or removable\nmedia auto-mount).\n\nReject the split whenever the chosen sp plus its declared size\nalready extends past hdr1->used.  This is the minimal fix; it\npreserves the existing hdr_find_split() contract and relies on the\nsame out: cleanup path as the pre-existing error returns.\n\nA prior OOB read in the very same indx_insert_into_buffer() memmove\nwas fixed in commit b8c44949044e (\"fs/ntfs3: Fix OOB read in\nindx_insert_into_buffer\") by tightening hdr_find_e(), but that fix\ndoes not cover the split-point size field path addressed here: sp is\nreturned by hdr_find_split(), not hdr_find_e(), and the underflow is\ndriven by sp->size rather than hdr->used exceeding hdr->total.","state":0,"publishedAt":"2026-08-15T05:53:51.893+00:00","modifiedAt":"2026-10-16T18:45:00.783+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                        \"fs/ntfs3/index.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"82cae269cfa953032fbb8980a7d554d60fb00b17\",\n                            \"lessThan\": \"8e4ba5a38c155bb3c1c11e63cd285b178cdb099e\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"82cae269cfa953032fbb8980a7d554d60fb00b17\",\n                            \"lessThan\": \"4c2f648139a0a86f4486170f72e24fedd4fae74e\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"82cae269cfa953032fbb8980a7d554d60fb00b17\",\n                            \"lessThan\": \"b232eb5c9fe11ec2368e9b565db69c724c35fbd2\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"82cae269cfa953032fbb8980a7d554d60fb00b17\",\n                            \"lessThan\": \"7bf74e6baf810fe325f111996496c678fc6e244f\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"82cae269cfa953032fbb8980a7d554d60fb00b17\",\n                            \"lessThan\": \"f3624cc069195001c88df7a291af215f2133ff2c\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"82cae269cfa953032fbb8980a7d554d60fb00b17\",\n                            \"lessThan\": \"1758a564b6ebe7f4a82f23c9851d1cae15549457\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"82cae269cfa953032fbb8980a7d554d60fb00b17\",\n                            \"lessThan\": \"f1df9d771df47aa40de6d70949c28720ae1e430d\",\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                        \"fs/ntfs3/index.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"5.15\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"5.15\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.217\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.184\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.145\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.97\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.40\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.1.5\",\n                            \"lessThanOrEqual\": \"7.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8,"severity":"CRITICAL"}],"references":["https://git.kernel.org/stable/c/8e4ba5a38c155bb3c1c11e63cd285b178cdb099e","https://git.kernel.org/stable/c/4c2f648139a0a86f4486170f72e24fedd4fae74e","https://git.kernel.org/stable/c/b232eb5c9fe11ec2368e9b565db69c724c35fbd2","https://git.kernel.org/stable/c/7bf74e6baf810fe325f111996496c678fc6e244f","https://git.kernel.org/stable/c/f3624cc069195001c88df7a291af215f2133ff2c","https://git.kernel.org/stable/c/1758a564b6ebe7f4a82f23c9851d1cae15549457","https://git.kernel.org/stable/c/f1df9d771df47aa40de6d70949c28720ae1e430d"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-72191","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-72191","identifiers":["CVE-2026-72191"]},"retained":false,"historicalAffected":[]}],"coverage":[]}