In this last part, we will compare Old Qealler with the new Qealler/Pyrogenic variant. The previous posts Pyrogenic Infostealer static analysis – Part 0x1 & Unpacking Pyrogenic/Qealler using Java agent -Part 0x2 went through the latest Pyrogenic/Qealler  statically and dumping the unpacked code using Java agent.
Based on ANY.RUN submissions, Old Qealler variant using the Qazagne stopped around April 2019
Based on ANY.RUN submissions, Qealler tagged samples started around Aug 2019 and continue till now Aug 2020.
Similarity between Qealler variants
For easy/fast comparison, I have imported unpacked code of both Qealler variant in Eclipse IDE. I will compare this Old Qealler (MD5: 8D564A18B902461C19936CCB1F4E2F12)  and new Pyrogenic/Qealler sample (MD5: F0E21C7789CD57EEBF8ECDB9FADAB26B)  used in the previous posts. Highly recommended to read through the existing analysis of Old Qealler Unloaded by @jeFF0Falltrades & article  by Zscaler.
Both Qealler variants use the same Qrypter packer variant.
1. AES Key bbb6fec5ebef0d93
You will find multiple references to bbb6fec5ebef0d93 as shown below. This is the AES key used in both variant.
2. UUID Key 2a898bc98aaf6c96f2054bb1eadc9848eb77633039e9e9ffd833184ce553fe9b
Config is stored in a key value pair and key for UUID present in both variants. This key is also present in the Old Qealler Unloaded article and the same string “Loaded:” is used in both variants.
3. Systeminfo in JSON format
It collects the system info in JSON format before encrypting and sending it to CC. Both Qealler variants use the same key e.g osName, osVersion, osArch, totalMemory and code structure as shown below. localIpAddress & globalIpAddress keys are added to the new Qealler version.
It is used when we want to run some code when JVM is shutting down and both variants use the addShutdownHook() to delete the files.
5. QeallerV4 string
Found this string “obfuscated/META-INF/QeallerV4.kotlin_module” in memory in the new Qealler/Pyrogenic sample. Maybe this is version 4 ?
In this Java malware analysis series we started with static analysis, then moved to Unpacking code using Java agent and in this last part we compared the Qealler variant. These above similarities are the most significant which I can find based on code analysis. I can conclude that the Malware author moved the Credential stealing from Python to Java based code. Malware authors are experienced coder as they divided the source code in multiple sensible packages and gave proper name to functions, variables and classes.
Hope you enjoyed this post, please Follow @Securityinbits me on Twitter to get the latest update about my malware analysis & DFIR journey. Happy Reversing 😊
- Tweet by @James_inthe_box – (MD5: 65ab1ef8e9cef5c489d4b01cbb8a2a22) First Old Qealler tweet Aug 2018
- Qealler Unloaded by @jeFF0Falltrades – Sep 2018
- Qealler – a new JAR-based information stealer – Feb 2019
- ANY.RUN – (MD5: 65ab1ef8e9cef5c489d4b01cbb8a2a22) Old Qealler June 2018
- ANY.RUN – (MD5: 8D564A18B902461C19936CCB1F4E2F12) Old Qealler Sep 2018
- ANY.RUN – (MD5: F0E21C7789CD57EEBF8ECDB9FADAB26B) New Qealler/Pyrogenic Nov 2019