exploit the possibilities

Signal Forced Call Acceptance

Signal Forced Call Acceptance
Posted Oct 5, 2019
Authored by Google Security Research, natashenka

There is a logic error in Signal that can cause an incoming call to be answered even if the callee does not pick it up.

tags | exploit
MD5 | cfd5f34a2c4720cf69df48f6e4d12c1c

Signal Forced Call Acceptance

Change Mirror Download
Signal: Incoming call can be connected without user interaction

There is a logic error in Signal that can cause an incoming call to be answered even if the callee does not pick it up.

In the Android client, there is a method handleCallConnected that causes the call to finish connecting. During normal use, it is called in two situations: when callee device accepts the call when the user selects 'accept', and when the caller device receives an incoming \"connect\" message indicating that the callee has accepted the call. Using a modified client, it is possible to send the \"connect\" message to a callee device when an incoming call is in progress, but has not yet been accepted by the user. This causes the call to be answered, even though the user has not interacted with the device. The connected call will only be an audio call, as the user needs to manually enable video in all calls. The iOS client has a similar logical problem, but the call is not completed due to an error in the UI caused by the unexpected sequence of states. I would recommend improving the logic in both clients, as it is possible the UI problem doesn't occur in all situations.

To reproduce this problem on the Android client, replace the method handleSetMuteAudio in the file WebRtcCallService.java with the following method.

private void handleSetMuteAudio(Intent intent) {

Log.e(TAG, \"SENDING MESSAGE\");

this.dataChannel.send(new DataChannel.Buffer(ByteBuffer.wrap(Data.newBuilder().setConnected(Connected.newBuilder().setId(this.callId)).build().toByteArray()), false));

intent.putExtra(EXTRA_CALL_ID, this.callId);
intent.putExtra(EXTRA_REMOTE_ADDRESS, recipient.getAddress());
handleCallConnected(intent);
}

Then build the client and install it and make a call. When the call is ringing, the audio mute button can be pressed to force the callee device to connect, and audio from the callee device will be audible.

This bug is subject to a 90 day disclosure deadline. After 90 days elapse
or a patch has been made broadly available (whichever is earlier), the bug
report will become visible to the public.





Found by: natashenka@google.com

Login or Register to add favorites

File Archive:

August 2020

  • Su
  • Mo
  • Tu
  • We
  • Th
  • Fr
  • Sa
  • 1
    Aug 1st
    3 Files
  • 2
    Aug 2nd
    2 Files
  • 3
    Aug 3rd
    32 Files
  • 4
    Aug 4th
    22 Files
  • 5
    Aug 5th
    15 Files
  • 6
    Aug 6th
    19 Files
  • 7
    Aug 7th
    6 Files
  • 8
    Aug 8th
    1 Files
  • 9
    Aug 9th
    2 Files
  • 10
    Aug 10th
    27 Files
  • 11
    Aug 11th
    8 Files
  • 12
    Aug 12th
    0 Files
  • 13
    Aug 13th
    0 Files
  • 14
    Aug 14th
    0 Files
  • 15
    Aug 15th
    0 Files
  • 16
    Aug 16th
    0 Files
  • 17
    Aug 17th
    0 Files
  • 18
    Aug 18th
    0 Files
  • 19
    Aug 19th
    0 Files
  • 20
    Aug 20th
    0 Files
  • 21
    Aug 21st
    0 Files
  • 22
    Aug 22nd
    0 Files
  • 23
    Aug 23rd
    0 Files
  • 24
    Aug 24th
    0 Files
  • 25
    Aug 25th
    0 Files
  • 26
    Aug 26th
    0 Files
  • 27
    Aug 27th
    0 Files
  • 28
    Aug 28th
    0 Files
  • 29
    Aug 29th
    0 Files
  • 30
    Aug 30th
    0 Files
  • 31
    Aug 31st
    0 Files

Top Authors In Last 30 Days

File Tags

Systems

packet storm

© 2020 Packet Storm. All rights reserved.

Services
Security Services
Hosting By
Rokasec
close