what you don't know can hurt you
Home Files News &[SERVICES_TAB]About Contact Add New

WebRTC usrsctp Incorrect Call

WebRTC usrsctp Incorrect Call
Posted Jul 31, 2020
Authored by Google Security Research

When usrsctp is used with a custom transport, an address must be provided to usrsctp_conninput be used as the source and destination address of the incoming packet. WebRTC uses the address of the SctpTransport instance for this value. Unfortunately, this value is often transmitted to the peer, for example to validate signing of the cookie. This could allow an attacker access to the location in memory of the SctpTransport of a peer, bypassing ASLR.

tags | advisory
advisories | CVE-2020-6514
SHA-256 | fd1aa95a1ad503592aea4e4e119465c590188163980b90ddc3e033c6ee7c80ec

WebRTC usrsctp Incorrect Call

Change Mirror Download
WebRTC: usrsctp is called with pointer as network address

When usrsctp is used with a custom transport, an address must be provided to usrsctp_conninput be used as the source and destination address of the incoming packet. WebRTC uses the address of the SctpTransport instance for this value. Unfortunately, this value is often transmitted to the peer, for example to validate signing of the cookie. This could allow an attacker access to the location in memory of the SctpTransport of a peer, bypassing ASLR.

To reproduce, place the following code on line 9529 of sctp_output.c. This will output the peer's address to the log:

struct sctp_state_cookie cookie2;
struct sctp_state_cookie* cookie3;
cookie3 = sctp_get_next_param(cookie, 4, &cookie2, sizeof(struct sctp_state_cookie));


LOGE(\"COOKIE INITACK ADDRESS %llx laddress %llx\", *((long long*)cookie3->address), *((long long*)cookie3->address));

Or, view the SCTP packets sent by WebRTC before they are sent to the encryption layer. They are full of pointers.

This bug is subject to a 90 day disclosure deadline. After 90 days elapse,
the bug report will become visible to the public. The scheduled disclosure
date is 2020-Jul-28. Disclosure at an earlier date is possible if
agreed upon by all parties.


Related CVE Numbers: CVE-2020-6514.



Found by: deadbeef@chromium.org

Login or Register to add favorites

File Archive:

March 2024

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

Top Authors In Last 30 Days

File Tags

Systems

packet storm

© 2022 Packet Storm. All rights reserved.

Services
Security Services
Hosting By
Rokasec
close