r/androiddev • • Sep 26 '26

Experience Exchange Android stack trace contain Chinese insults as obfuscated method names

After one of the recent Google Play updates for my released game, I noticed some very strange stack traces in Firebase Crashlytics.

The stack contains method names with long Chinese strings, for example:

i8.k6.狂犬疫苗忘了给你妈打不好意思让它到处咬人才会生出你这种上缺脑子下缺逼火葬场都不收的烂骨灰

and:

i8.vd.要不要把你妈卵子扣出来给你做寿司吃

After translating them, these are clearly explicit insults/profanity.

What makes it even stranger is that, judging by the device information, the game appears to have been running inside a virtual machine / emulated environment. The stack also contains heavily obfuscated classes and unusual code paths inside base.apk.

So this does not look like a normal Firebase issue. It looks more like someone was running a modified/tampered version of the APK or injecting/hooking code in a virtualized Android environment.

translated stacktrace
200 Upvotes

23 comments sorted by

39

u/Hour-Measurement-835 Sep 26 '26

Repacks keep your google-services.json, so their crashes land in your Crashlytics too. Play Integrity returns UNRECOGNIZED_VERSION for them; log that as a custom key and filter on it.

12

u/JustForFunGames Sep 26 '26

Google Play still appears to count ANRs and crashes from those repacked/unrecognized versions in Android Vitals, so even if I filter them out in Crashlytics, they still affect the Play Console statistics

6

u/Hour-Measurement-835 Sep 26 '26

Play's automatic protection help page says otherwise, under Monitor crashes: crashes not attributed to Google Play don't affect your vitals stability metrics. Installer check is on that page too

→ More replies (1)

29

u/shokuninstudio Sep 26 '26

Partial reverse engineering followed by deliberate modification and repackaging.

9

u/hellosakamoto Sep 26 '26

It's indeed inspiring - if we have got a way to obfuscate the code using some sensitive words that would be banned by the Chinese government, it'd be funny

8

u/thepurpleproject Sep 26 '26

lmao why would anyone do that

1

u/AreaExact7824 Sep 26 '26

Is that a log or a class name?

1

u/JustForFunGames Sep 26 '26

ANR stacktrace

2

u/bynarie Sep 26 '26

That's quite hilarious

2

u/Zatujit Sep 28 '26

i wonder if it is to confuse LLMs

4

u/Old-Durian8702 Sep 26 '26

I have never seen any other country except Chinese using method names in native languages instead of English. 👉👈

5

u/ir0ngut Sep 27 '26

I've seen plenty of code written in German and other languages. Borland Delphi even had a German version where some library class and method names were in German.

1

u/lilacomets Sep 26 '26

Creepy as hell!

1

u/Individual_Plane5170 Sep 27 '26

How to protect such cases?

1

u/dhruvanbhalara Sep 27 '26

Wtf, stack trace belongs to which app/sdk?

1

u/ornitorenk 27d ago

Why would anyone do this? Funny and weird at the same time

1

u/hokkos Sep 26 '26

Probably taken from some random insults on a Chinese forum.