Bug Chaining worth $500! šŸ¤‘

th3.d1p4k
3 min readAug 19, 2021

Hellow bug hunters! Iā€™m back again with another writeup. Mostly I donā€™t show off my bountiesšŸ¤‘ . But this writeup is not for bounty purpose. Iā€™ll tell you what mistakes I have done and which you shouldnā€™t repeat for the same bug like I did. Iā€™ll also share with you some tips and obviously bug chaining. So, without any delay letā€™s start roller coaster ride. šŸ˜‰

I was hunting on responsible program. That program has very less features. I mean there was no signup or login functionality or similar input field where I can test bugs. There are only few web pages like you can download that companyā€™s software and read manual, privacy policy, etc. Now what?

I fired up Burpsuite (Burpi ā¤) and spider the whole website. Then suddenly I see that there are no more security headers. Specially XSS protection header. As you know about target there is no functionality to test input validation. There was language/email parameter (e.g. target.com/?lang=en&email=x). I know what you are thinking right now. And I tried simple XSS payload and it worked!! Woohooā€¦ šŸ˜

Great? Haha no. Self XSS was out of scope

I started bug chaining. I did HTML Injection. I typed simple HTML code (e.g.<h1>HelloWorldHTMLInjectionHere</h1>) and its executed. What else we can do? Another bug chain is Open redirection via HTML Injection. Yes, you read it right. Payload will look like below:

<script>document.location.href=ā€https://example.comā€</script>

It will redirect to the example.com. I quickly made poc and write a good report and send it to their security mail. After couple of days I got mail that I am eligible for bounty. And I got 500$. Thatā€™s it guys. Keep hunting, Keep Sharing.

Mistakes I had done while testing. There were more than 6 domains which are related to target company. And same bug was there. But I reported only one main domainā€™s bug and they fixed remaining domains which were also affected to the same bug.

Lesson: If you find a bug check same parameters on in-scope domains.

Bhaari nuksan ho gaya hamara!

Tip: If Self XSS is out of scope then you can try HTML Injection, Open Redirection, CSRF, Self XSS to Stored XSS.

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Twitter: Dipak Panchal

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