Added Sentry debugging, getting long string as undefined

Question

We're building a Angular 1.x app with Bootstrap components. We recently added Sentry debugging to site and just got this error:

'PAPADDINGXXPADDINGPADDINGXXPADDINGPADDINGXXPADDINGPADDINGXXPADDINGPADDINGXXPADDINGPADDINGX' is undefined

browser = IE 11.0
device = Other
level = error
logger = javascript
os = Windows 8.1

Mozilla/5.0 (Windows NT 6.3; WOW64; Trident/7.0; .NET4.0E; .NET4.0C; .NET CLR 3.5.30729; .NET CLR 2.0.50727; .NET CLR 3.0.30729; InfoPath.3; MDDCJS; rv:11.0) like Gecko

I found a couple of references on Twitter but nothing else. Anyone seen this before? How can I fix this?

It appears others are experiencing this as well (including my company, just today): https://twitter.com/dpaola2/status/491433981942829057 — John Washam, Jun 21 '16 at 18:33
Any ideas? Only on IE11 - still seeing this pop up sometimes — tim, Mar 28 '17 at 22:23
Seen today from IE11 on windows 8.1. Looks like hacker activity but doesn't seem to be. — markus, Nov 02 '17 at 22:09
Possibly related? https://social.msdn.microsoft.com/Forums/sqlserver/en-US/65abb72a-9d4f-4881-a534-6f75c4b8b498/unknown-error-in-visual-studio-express-2012-for-web?forum=vsdebug — chiliNUT, Nov 02 '17 at 22:32
When you remove the `sentry` from the site, does the error disappear? — Ivan Sivak, Nov 04 '17 at 21:04

Syed Ekram Uddin · Answer 1 · 2017-11-09T19:49:22.320

That's probably a malware works, mostly reported on windows platform. As you can see from the question, comments and from the internet; all reported for windows systems. According to few malicious activity logging/analysis/reporting service (see ref links below); the malware writes/ends the file with a series of “PADDINGPADDINGXX” strings.

Search in extracted strings section of following sites

A "probably" won't do :-) We already know that all reported systems are Windows 8 and I think all reported browsers are IE11. So that's nothing new. I want somebody to break open one of these wares and show us the insides. — markus, Nov 03 '17 at 18:00
Thats for collaboration, So that i can update post accordingly. I also noticed that same thing reported on other sites in similar or near by time of 2016. Wondering such thing still happening. — Syed Ekram Uddin, Nov 03 '17 at 19:02

score 3 · Answer 2 · answered Nov 09 '17 at 19:23

This is a speculative answer. But I intend this to be a resource collection of links pointing towards understanding this issue. Feel free to improve this!

Malware analysis of rtfn.exe
Visual Studio error :: Error occurring due to one click amazon toolbar
Bloated application size
Releasing a game for different platforms :: It states the following:

ac2game.dat is just your windows .exe renamed. You can snip out the unnecessary executable parts by opening it in a hex editor and searching for the string "PADDING". There is a block of text that repeats "PADDINGXX" for a bit, then "CLIB". Chop out everything before CLIB (but leave CLIB). This saves a little space.
Extracting resources with dlls
4 lines PADDINGXX at the end of executable
interesting IRC log

It's always good to sumble upon a good 1.8k block of "PADDINGXXPADDINGXXPADDINGXX"

All of this leads me to believe that this occurs when memory is allocated, but not utilised. So in your case IE spaghetti code must have picked up some of this.

Added Sentry debugging, getting long string as undefined

2 Answers2