CVE-2026-72195
HighCVSS 7.8Exploitation Probability (EPSS)
Low risk6th percentile - higher than 6% of all known CVEs
Summary
In the Linux kernel's NTFS3 filesystem, the UpdateResidentValue function did not validate the attribute offset, potentially leading to data size underflow and out-of-bounds read. The fix adds validation at the source.
Risk Assessment
An attacker could exploit this vulnerability to cause kernel crash or potentially read memory out of bounds, leading to privilege escalation.
Recommendation
Apply the Linux kernel update containing this fix. Restrict access to mounting untrusted NTFS filesystems.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: bound attr_off in UpdateResidentValue against data_off In do_action()'s UpdateResidentValue case (fslog.c:3307), lrh->attr_off and lrh->redo_len come from the on-disk LRH. When they satisfy aoff + dlen < attr->res.data_off, the assignment attr->res.data_size = cpu_to_le32(aoff + dlen - data_off); underflows to ~4 GiB (e.g. 0xFFFFFFF9 when aoff=0x10, dlen=1, data_off=0x18). Subsequent code that reads attr->res.data_size to walk the resident attribute payload would then read up to 4 GiB past the 1024-byte MFT record allocation. The existing mi_enum_attr() defense in fs/ntfs3/record.c:287 catches the corrupted data_size on the next attribute walk and fails the mount, but only on the path that walks all attributes. A read site that picks an attribute by name and reads its data_size without re-validating is not covered. Validate aoff against data_off and asize at the source. Reproduced under UML+KASAN on mainline 8d90b09e6741 via pr_warn-only probe: with aoff=0x10 and data_off=0x18, the post-assignment data_size is 0xfffffff9 (mount then fails at -22 from mi_enum_attr). [[email protected]: clang-formatted the changes]