{"id":"CVE-2026-89782","published":"2026-09-16T09:17:08.800","lastModified":"2026-09-16T15:18:08.577","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nfs/ntfs3: reject restart table growth beyond U16_MAX entries\n\nDuring $LogFile replay, log_replay() indexes the transaction table by the\ntransact_id taken from the log record header.  check_log_rec() only\nverifies that transact_id is non-zero and properly aligned, not its\nmagnitude, so a crafted image can request an arbitrarily large index.\n\nalloc_rsttbl_from_idx() grows the table to cover that index via\nextend_rsttbl(), which passes the new entry count to init_rsttbl():\n\n\trt = init_rsttbl(esize, used + add);\n\nused + add is computed as u32 but init_rsttbl() takes a u16, and the\ncount is stored in struct RESTART_TABLE as a __le16.  When used + add\nexceeds U16_MAX it is truncated, init_rsttbl() allocates a table far\nsmaller than the index requires, and alloc_rsttbl_from_idx() then\ndereferences and writes at the original, untruncated offset -- an\nout-of-bounds access past the allocation, reachable by mounting a\ncrafted NTFS image.\n\n BUG: KASAN: use-after-free in alloc_rsttbl_from_idx (fs/ntfs3/fslog.c:950)\n Read of size 4 at addr ffff8880327ffff8 by task exploit\n  alloc_rsttbl_from_idx (fs/ntfs3/fslog.c:950)\n  log_replay (fs/ntfs3/fslog.c:4562)\n  ntfs_loadlog_and_replay (fs/ntfs3/fsntfs.c:324)\n  ntfs_fill_super (fs/ntfs3/super.c:1393)\n  get_tree_bdev_flags\n  vfs_get_tree\n  path_mount\n  __x64_sys_mount\n\nA restart table is limited to U16_MAX entries by its __le16 count, so a\nlarger growth request is invalid input.  Reject it in extend_rsttbl();\nall callers already handle a NULL return.","cvssScore":8.4,"cvssSeverity":"HIGH","cvssVector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/111f8d74a19d85942ecbb3aba78f6f3c88e59391","tags":[]},{"url":"https://git.kernel.org/stable/c/339e59996ff193adcf1c438cf05f19e753beb3a7","tags":[]},{"url":"https://git.kernel.org/stable/c/967a5ff8a614d10126b6d46db1ac040948d6cb42","tags":[]},{"url":"https://git.kernel.org/stable/c/aad605a450611e2a7b7cf9dd5724004d39192bfb","tags":[]},{"url":"https://git.kernel.org/stable/c/be218a01aadffe33ed4fc73e25276d676ebbd09d","tags":[]},{"url":"https://git.kernel.org/stable/c/caa0ec3fc44a13d7c21d78e4722f4f05f87ccf56","tags":[]},{"url":"https://git.kernel.org/stable/c/ecde45cd81dc28f5696c312c5ce5a509962e9ab1","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}