unshare

Execute a command in new user-defined namespaces. tldr-pages

GTFOBins shell 1 ATT&CK technique 1 documented command

How unshare is abused

documented by GTFOBins

shell T1059.004 Command and Scripting Interpreter: Unix Shell

Each abuse is GTFOBins's category and the options and words it uses; the full write-up is on GTFOBins's page for unshare.

1 documented command

from GTFOBins, each read by the identifier

shell unprivileged, with sudo, as SUID

unshare /bin/sh

Identify

As SUID:

unshare -r /bin/sh

The command the identifier reads trips no Sigma process-creation rule. This command is from GTFOBins, at commit acd524623f9c of 2026-05-27, under the GPL-3.0, with no warranty. Changed: Markdown is shown formatted. The source is in lolbas-gtfobins-commands.json.gz, and the full entry is on GTFOBins’s page for unshare. The identifier reads the line that runs unshare.

What detects it

Sigma process creation rules

T1059.004Command and Scripting Interpreter: Unix Shell

Everyday use

from tldr-pages, CC BY 4.0

Execute the default shell

unshareIdentify

Execute a command without sharing access to connected networks

sudo unshare --net command argument1 argument2 ...Identify

Execute a command as a child process without sharing mounts, processes, or networks

sudo unshare [-mpnf|--mount --pid --net --fork] command argument1 argument2 ...Identify

None of the 3 examples the identifier reads matches GTFOBins abuse or trips a Sigma process-creation rule.

Options

10 in toybox

Show every option of unshare

-aUnshare all supported namespaces

-fFork command in the background (--fork)

-rBecome root (map current euid/egid to 0/0, implies -U) (--map-root-user)

-CControl groups (--cgroup)

-iSysV IPC (message queues, semaphores, shared memory) (--ipc)

-mMount/unmount tree (--mount)

-nNetwork address, sockets, routing, iptables (--net)

-pProcess IDs and init (--pid)

-uHost and domain names (--uts)

-UUIDs, GIDs, capabilities (--user)