CHFI Computer Forensics Investigation Process Practice Question

Exhibit

Refer to the exhibit.

C:\> fsutil volume dismount C:

C:\> diskpart
DISKPART> select volume 1
DISKPART> attribute volume clear readonly
DISKPART> exit

C:\> e2fsck -fn image.dd

e2fsck 1.45.6 (20-Mar-2020)
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
image.dd: ********** WARNING: Filesystem still has errors **********

An analyst executed the commands shown in the exhibit on a Windows system to prepare a forensic image for analysis. What is the most likely reason for the error message from e2fsck?

⚠ Common exam trap

EC-Council often tests the misconception that a write-blocker alone guarantees a forensically sound image, but the trap here is that even with a write-blocker, imaging a mounted volume can produce an inconsistent filesystem because the OS may have pending writes in cache.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

The analyst failed to properly dismount the source volume before imaging, leading to filesystem inconsistencies.

The error message from e2fsck indicates that the filesystem has inconsistencies, which typically occur when a volume is imaged while it is still mounted and actively being written to. The analyst likely did not dismount the source volume before acquiring the forensic image, resulting in a snapshot that reflects an inconsistent state (e.g., dirty journal, unflushed writes). This is a common chain-of-custody and acquisition procedure error in forensic imaging.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✓
The analyst failed to properly dismount the source volume before imaging, leading to filesystem inconsistencies.
Why this is correct
The sequence shows `fsutil dismount` being run on C:, but a forensic image taken afterward—especially after Windows remounts the volume or during a live acquisition—will capture the volume in an inconsistent state. When Windows later performs recovery on the dirty volume, metadata updates begin immediately, so e2fsck in the analyst's analysis environment will legitimately report superblock, group descriptor, or inode inconsistencies that were never present in the source. This is the classic 'dirty volume' imaging error, not a problem with the image tool.
✗
The forensic image was not acquired with a write-blocker, causing data corruption.
Why it's wrong here
The absence of a dedicated hardware write-blocker is a limitation of the acquisition chain, but the command history here shows `diskpart` operations, not the actual imaging utility; there is no evidence that the source drive was written to during acquisition. Corruption from a missing write-blocker would manifest as read errors or altered hash values in the original device, not as filesystem-integrity errors reported by e2fsck from inside the image. The e2fsck findings point to an inconsistency in the filesystem state itself, which is directly explained by an unclean dismount, rather than by external hardware writes.
✗
The image file contains an NTFS filesystem, but e2fsck is designed for ext filesystems.
Why it's wrong here
e2fsck is designed for ext-family filesystems, but it does not simply 'work on NTFS'; it first validates the superblock magic number and would immediately terminate with a message like 'Couldn't find a valid filesystem superblock' or 'bad magic number'. The detailed errors about group descriptors, inode bitmaps, or the like are ext-specific structures, so the image must actually contain an ext filesystem that was imaged while inconsistent. Therefore, the problem is not that the tool was run on NTFS; the tool's output itself proves the media is ext-based.
✗
The e2fsck command syntax is incorrect; it should be 'e2fsck -f -n' instead.
Why it's wrong here
The invocation `e2fsck -fn` is a valid and common shorthand; like `-f -n` it forces the check even if the filesystem is marked clean and opens the filesystem read-only so no changes are made. Combined single-letter switches are standard for e2fsck, so `-fn` is not the reason the check surfaces recoverable inconsistencies. If the analyst had used `-p` or omitted `-n`, the tool might have written repairs, but that would be a separate operational concern, not a syntax error.

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CHFI Computer Forensics Investigation Process Practice Question

Exhibit

Why each option matters

Option-by-option breakdown

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