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Home Page Forums General Discussions Good ways to avoid Self-XSS ?

  • Good ways to avoid Self-XSS ?

    Posted by Deleted User on June 21, 2021 at 5:41 pm

    Hello everyone, my problem in the past is thinking i have found a XSS vulnerability, but it turned out to be Self-XSS. I learned that going through the console and manipulating the “Source Code” for example a mouseover or JavaScript:alert() to force a pop-up. It worked but in the end turned out to be a self-xss which i did not know at the time what it was. But now i try to avoid these all too common problems is there some good techniques and ways to avoid this mistake again, thank you.

    Deleted User replied 3 years, 3 months ago 2 Members · 2 Replies
  • 2 Replies
  • Christophe

    Administrator
    June 23, 2021 at 9:26 pm

    Hey Anthony, couple of answers from two different perspectives:

    From the bug bounty perspective:

    1- One way to avoid submitting self-XSS in bug bounty programs that don’t have a measurable impact is to think about how the vulnerability you are submitting in your report gets exploited. What actions does an attacker have to take in order to exploit this XSS vulnerability? Does it require another user’s interaction? If so, what would the user have to do to trigger it? Would they have to copy/paste the payload in their own browser console? If so, that’s self-XSS. In addition to that, think about how you would do something practical with that vulnerability. ie: here’s exactly how I would steal an admin’s credentials, or here’s how I would steal a user’s billing information.

    So before I submit a report, I always try to answer – in detail – the question: “How would I successfully exploit this vulnerability if I wanted to do damage?” If I can’t answer that question in my report, my work isn’t done yet and I don’t have a proper report.

    From the victim of self-XSS perspective:

    2- One way to avoid being the victim of self-XSS social engineering is to never copy/paste code that someone gives you in your browser’s console unless you are 100% certain of what it does. Though honestly, this applies to copy/pasting code even outside of your browser.

    • Deleted User

      Deleted User
      June 24, 2021 at 4:54 pm

      Hmm you gave me a lot to think about on this issue.

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