Can You Read a File Without Directory Execute Permission? Linux Explained

Linux Permission Basics

Linux assigns three basic bits to files and directories: read (r) , write (w) , and execute (x) . The meaning differs slightly between files and directories:

Read (r) : on a file, allows the contents to be displayed; on a directory, permits listing the entries.

Write (w) : on a file, permits modifying its contents; on a directory, permits creating, renaming or deleting entries.

Execute (x) : on a file, allows it to be run as a program; on a directory, allows the user to "enter" the directory and access objects inside it.

Scenario: File readable but parent directory not executable or readable

Consider a user who has r permission on secret.txt but lacks both r and x permissions on the directory /data/private that contains the file.

No execute permission on the directory ( x ) : Without x, the user cannot traverse into the directory. Even if the exact pathname /data/private/secret.txt is known, the kernel blocks the lookup, so the file cannot be opened.

No read permission on the directory ( r ) : Lacking r prevents the user from listing the directory’s contents with ls. If the user somehow already knows the full pathname, access would still require the directory’s x permission, which is missing.

Typical command‑line illustration

# Create a file readable only by its owner
chmod 600 secret.txt
# Remove read and execute bits from the containing directory for group/others
chmod 700 /data/private
# Attempt to read the file as a non‑owner
su - otheruser
cat /data/private/secret.txt   # → Permission denied

Key Takeaway

Accessing a file requires:

Read permission on the file itself (if the operation is a read).

Execute permission on every directory component of the path.

Read permission on a directory only when the user needs to list its entries.

If any directory in the path lacks x, the lookup stops and the file remains inaccessible, regardless of the file’s own permissions.

Practical Use

System administrators can protect sensitive files by removing the execute bit from the parent directory while still granting the file’s owner read access. Users who know the exact pathname can be allowed to read the file only after the directory’s execute permission is restored for them (e.g., via ACLs or group membership).