{"id":"CVE-2026-72195","summary":"fs/ntfs3: bound attr_off in UpdateResidentValue against data_off","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nfs/ntfs3: bound attr_off in UpdateResidentValue against data_off\n\nIn do_action()'s UpdateResidentValue case (fslog.c:3307),\nlrh-\u003eattr_off and lrh-\u003eredo_len come from the on-disk LRH.\nWhen they satisfy aoff + dlen \u003c attr-\u003eres.data_off, the\nassignment\n\n\tattr-\u003eres.data_size = cpu_to_le32(aoff + dlen - data_off);\n\nunderflows to ~4 GiB (e.g. 0xFFFFFFF9 when aoff=0x10, dlen=1,\ndata_off=0x18).  Subsequent code that reads attr-\u003eres.data_size\nto walk the resident attribute payload would then read up to\n4 GiB past the 1024-byte MFT record allocation.\n\nThe existing mi_enum_attr() defense in fs/ntfs3/record.c:287\ncatches the corrupted data_size on the next attribute walk\nand fails the mount, but only on the path that walks all\nattributes.  A read site that picks an attribute by name and\nreads its data_size without re-validating is not covered.\nValidate aoff against data_off and asize at the source.\n\nReproduced under UML+KASAN on mainline 8d90b09e6741 via\npr_warn-only probe: with aoff=0x10 and data_off=0x18, the\npost-assignment data_size is 0xfffffff9 (mount then fails\nat -22 from mi_enum_attr).\n\n[almaz.alexandrovich@paragon-software.com: clang-formatted the changes]","modified":"2026-08-18T03:56:21.914671859Z","published":"2026-08-15T05:53:54.869Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72195.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/50b5e83384e7fed3d11d18b79ff350e9d6d89861"},{"type":"WEB","url":"https://git.kernel.org/stable/c/53c12f178f584dc5f836ffe2782138a6e9348ed9"},{"type":"WEB","url":"https://git.kernel.org/stable/c/546518468e6c9ea469669eef78f8cc380ad6e2ca"},{"type":"WEB","url":"https://git.kernel.org/stable/c/97758fd9756b5f09e9ddc6a5f6a569041acc8421"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a89c66674283a0293c0f266dc57087a6114371a3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ab8761676d638c5be170aaf91b7ffdd451236616"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d1570c48f49a693974d000251030370ee2e83539"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72195.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-72195"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"b46acd6a6a627d876898e1c84d3f84902264b445"},{"fixed":"ab8761676d638c5be170aaf91b7ffdd451236616"},{"fixed":"53c12f178f584dc5f836ffe2782138a6e9348ed9"},{"fixed":"546518468e6c9ea469669eef78f8cc380ad6e2ca"},{"fixed":"97758fd9756b5f09e9ddc6a5f6a569041acc8421"},{"fixed":"50b5e83384e7fed3d11d18b79ff350e9d6d89861"},{"fixed":"a89c66674283a0293c0f266dc57087a6114371a3"},{"fixed":"d1570c48f49a693974d000251030370ee2e83539"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-72195.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.15.0"},{"fixed":"5.15.212"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.178"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.145"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.97"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.40"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-72195.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}