chmod 127 Permission Explained

Notice: This is an unusual permission set: some classes have more access than the class above them. It is rarely correct in practice.
Octal
127
Symbolic
--x-w-rwx
Binary
001 010 111
Risk Level
Critical Risk

Summary: chmod 127 gives the owner execute, the group write, and everyone else read/write/execute.

Class Read (4) Write (2) Execute (1) Octal
Owner (u) 1
Group (g) 2
Others (o) 7
127
--x-w-rwx
Owner: execute · Group: write · Others: read/write/execute
chmod 127 filename
Critical Risk Anyone on the system can modify or replace this file.
View the full chmod 127 guide →
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chmod 127 Breakdown

Class Digit Symbolic On a file On a directory
Owner (u) 1 --x Execute only Can enter (cd) but not list contents
Group (g) 2 -w- Write only (rarely useful) No practical effect without x
Others (o) 7 rwx Full access Full access: list, enter, create, delete

Is chmod 127 Safe?

Critical Risk

Common Use Cases

127 is uncommon in standard Linux setups. The closest widely used permission is chmod 777.

chmod 127 Command Examples

# Apply using octal mode
chmod 127 filename

# Apply using equivalent symbolic mode
chmod u=x,g=w,o=rwx filename

# Recursive command warning:
chmod -R 127 /path/to/dir
# Note: -R applies the same mode to files and directories. Use find to treat them separately:
find /path/to/dir -type d -exec chmod 127 {} +

# Verify permissions
stat -c '%a %A %n' filename    # Linux
stat -f '%Lp %Sp %N' filename   # macOS

# Example ls -l output:
---x-w-rwx 1 alice staff 1024 Jan 15 10:00 example.txt

umask Relationship

A umask of 650 makes new directories 127. Test umask values with our interactive Umask Calculator.

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Frequently Asked Questions

What does chmod 127 mean?

chmod 127 gives the owner execute, the group write, and everyone else read/write/execute. In octal notation, the owner receives 1 (execute), the group receives 2 (write), and others receive 7 (read/write/execute).

Is chmod 127 safe?

chmod 127 is classified as Critical Risk. Anyone on the system can modify or replace this file.

What is chmod 127 in symbolic notation?

In symbolic notation, chmod 127 is represented as --x-w-rwx. You can apply this permission using the equivalent symbolic command "chmod u=x,g=w,o=rwx filename".

Related Permissions

Change one bit:

← chmod 126 chmod 130 →

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