In the Linux kernel, the following vulnerability has been resolved:
ntfs: sanitize MFT references returned from ntfs_lookup_inode_by_name()
ntfs_lookup_inode_by_name() returns MFT references read from directory
index entries on disk. These values are untrusted, but the function can
currently return an error-marked MFT reference to its callers without
validating it.
Callers later decode lookup failures with MREF_ERR(). A crafted NTFS image
can set the MREF error bit while leaving the low bits as an arbitrary
value, causing callers to consume a bogus pseudo-errno instead of treating
the lookup result as corrupted on-disk metadata.
Fix this at the source by normalizing every error-marked MFT reference
returned from ntfs_lookup_inode_by_name() to ERR_MREF(-EIO). Apply this to
all four directory lookup return paths so every caller gets a validated
result without needing additional checks or an API change.
This keeps the sanitization in the common lookup helper, which is cleaner
than duplicating validation in each caller.
CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
CVSS Score: 9.1
AV:N - fs/ntfs registers ntfs_export_ops; remote nfsd/ksmbd LOOKUP/OPEN/stat on an exported crafted NTFS volume reaches ntfs_lookup→ntfs_lookup_inode_by_name parsing attacker-controlled INDX indexed_file values without local shell access.
AC:L - The attacker fully controls on-disk directory index indexed_file MFT references and can set the ERR_MREF error bit with arbitrary low bits; decoding the forged pseudo-errno via MREF_ERR() is deterministic from a crafted image with no race or external timing.
PR:N - Triggering needs only a malicious NTFS image (USB, loop, dual-boot disk) mounted by the host or lookup access to exported NTFS paths via NFS/SMB; no init-namespace root or CAP_SYS_ADMIN is required on the code path that consumes the bogus errno.
UI:N - fill_super mount-time lookups (hiberfil.sys, $Quota) and subsequent local or remote path lookups call ntfs_lookup_inode_by_name as soon as the crafted volume is mounted or exported, without further per-attack cooperation beyond volume presentation.
S:U - Forged errno handling perturbs VFS lookup and mount safety decisions within the host kernel/filesystem authority only; this is standard filesystem parsing abuse, not a VM escape, IOMMU bypass, or cross-security-boundary scope change.
C:N - The flaw only mis-decodes error-marked MFT references into attacker-chosen errno values returned to callers; there is no out-of-bounds read, use-after-free, or other kernel memory disclosure primitive.
I:H - Spoofing -ENOENT via error-bit indexed_file can add negative dentries for present index entries and make check_windows_hibernation_status/load_and_init_quota treat hiberfil.sys/$Quota as absent, bypassing hibernation/quota guards and permitting rw corruption of live Windows hibernation and NTFS metadata.
A:H - Hibernation-check bypass allows rw I/O on a suspended Windows volume, corrupting hiberfil.sys and preventing resume; forged lookup errnos also leave persistent negative-cache and index inconsistencies that can render the volume or dependent OS unusable.
| Attack Vector |
Network |
Scope |
Unchanged |
| Attack Complexity |
Low |
Confidentiality Impact |
None |
| Privileges Required |
None |
Integrity Impact |
High |
| User Interaction |
None |
Availability Impact |
High |
AV:N - fs/ntfs registers ntfs_export_ops; remote nfsd/ksmbd LOOKUP/OPEN/stat on an exported crafted NTFS volume reaches ntfs_lookup→ntfs_lookup_inode_by_name parsing attacker-controlled INDX indexed_file values without local shell access.
AC:L - The attacker fully controls on-disk directory index indexed_file MFT references and can set the ERR_MREF error bit with arbitrary low bits; decoding the forged pseudo-errno via MREF_ERR() is deterministic from a crafted image with no race or external timing.
PR:N - Triggering needs only a malicious NTFS image (USB, loop, dual-boot disk) mounted by the host or lookup access to exported NTFS paths via NFS/SMB; no init-namespace root or CAP_SYS_ADMIN is required on the code path that consumes the bogus errno.
UI:N - fill_super mount-time lookups (hiberfil.sys, $Quota) and subsequent local or remote path lookups call ntfs_lookup_inode_by_name as soon as the crafted volume is mounted or exported, without further per-attack cooperation beyond volume presentation.
S:U - Forged errno handling perturbs VFS lookup and mount safety decisions within the host kernel/filesystem authority only; this is standard filesystem parsing abuse, not a VM escape, IOMMU bypass, or cross-security-boundary scope change.
C:N - The flaw only mis-decodes error-marked MFT references into attacker-chosen errno values returned to callers; there is no out-of-bounds read, use-after-free, or other kernel memory disclosure primitive.
I:H - Spoofing -ENOENT via error-bit indexed_file can add negative dentries for present index entries and make check_windows_hibernation_status/load_and_init_quota treat hiberfil.sys/$Quota as absent, bypassing hibernation/quota guards and permitting rw corruption of live Windows hibernation and NTFS metadata.
A:H - Hibernation-check bypass allows rw I/O on a suspended Windows volume, corrupting hiberfil.sys and preventing resume; forged lookup errnos also leave persistent negative-cache and index inconsistencies that can render the volume or dependent OS unusable.
CVSS 3.1