Coordinated and Responsible Vulnerability Disclosure Free Bug Bounty Program 343,169 coordinated disclosures
197,155 fixed vulnerabilities
469 bug bounties with 943 websites
9,678 researchers, 871 honor badges

login_denied Top VIP Security Researcher Top Security Researcher of the Month Top VIP Security Researcher of the Month | Security Researcher Profile

Security researcher login_denied has already helped fix 6882 vulnerabilities.

Researcher reputation:  1080

Real name:

About me:
Mathematician from Germany

How to contact me:
[email protected]

Experience in Application Security
1-3 years

Award / Bug Bounty I prefer:
Bounty Payment (e.g. PayPal via [email protected]);
Swag (T-shirt, cup, gimmick);
Recognition, thanks, fame;
Feedback would be nice.

Follow me on:

Recommendations and Acknowledgements | Full List:

    5 April, 2019
     YanezDeGomorra Antonio Ranesi from
Thanks you for your report on my website and and for your kind availability in providing the details immediately.
    3 April, 2019
     myparadisio Yves from Paradisio:
Thanks for pointing out the vulnerabilty on our website, login_denied!
    12 March, 2019
     cvetochnica_flo Maksim from FDW Ltd.:
Grateful for the bug! Found bug witch others did not find. And pleasant to talk to.
    11 March, 2019
     samueldebacker Samuel from Typi:
Thank you Andre, we now have fixed the XSS issue you found.
    3 March, 2019
     eco_sapiens kidsinhalf from eco-sapiens:
Thanks ! Very professionnal and helpful
    1 March, 2019
     ILT2010 Dave from Spectronics:
Thank you login_denied for disclosing the XSS issue and the prompt professionally detailed info/PoC that initiated the fix.
    27 February, 2019
     Timo_Ket Timothee from Smart&Soft:
Thanks for your kind an prompt help with fixing XSS on our site !
    25 February, 2019
     cyberday_gmbh DLO from CYBERDAY GmbH:
thanks for reporting
    22 February, 2019
     artentino Pablo from Artentino:
Login_denied warned us about an issu an issue in our site which has been fixed. We\'re very grateful to him and we highly recommend him! Cheers!
    20 February, 2019
     BullionInvestor Norman from BullionInvestor:
Thank you Andre for your faithful support to find & fix an XSS vulnerability I haven\'t noticed.
    31 January, 2019
     MihirGosai Admin from APKLinker:
Thanks for reporting vulnerability issues to APKLinker.
    29 January, 2019
     kovnickg Nick from FreshIT:
Andre reported about a XSS issue on our web site and provide detail by email. Thanks for making the internet safer!
    14 January, 2019
     watergateweb Alexios Tsiaparas from Watergate:
Thanks Andre for providing a very professional service. Your report provided all the information that we needed in order to rectify the XSS vulnerability that you have discovered.

Many thanks again!
    10 January, 2019
     deepthoughts10 Brian Clark from GC:
Thank you Andre for notifying us of the XSS issue you found but also in your quick reply with details that allowed us to isolate and fix the problem.
    7 January, 2019
     _light_dem Matteo from Mys:
Very professional and fast on reply, , it allowed us to find a xss vulnerability
    3 December, 2018
     rowlandarcher Rowland from Hittin' The Web Group LLC:
Very professional and responsive, helped me pinpoint and patch an XSS vulnerability. Great to work with, recommended.
    27 November, 2018
     OdedOfek Oded from N/A:
Andre made us aware of a security issue we hadn't found before and we're now working on fixing it. Thanks Andre for being one of the god guys :-)
    30 October, 2018
     RCikryt Roman from N/A:
Hi Andre, thank you very much for XSS notification and details. I have just fixed it. Thanks a lot!
    3 October, 2018
     andymarkelow Andrei Markelow from Online Buddies Inc.:
Thanks to Andre we could fix the vulnerability issue which was never discovered since many years!
    21 August, 2018
     EdgeMediaNet DevTeam from EDGE Media Network:
Andre was fantastic to work with. His feedback was valuable in finding issues on our sites. Friendly and very quick to answer. Highly recommended!!
    21 August, 2018
     cb_ximo Kino from pista3:
Andre found out a vulnerability on our site. With his help we have solved it. Thanks a lot
    15 August, 2018
     aboros Boris from Officeshoes:
Andre discovered a XSS vulnerability on our web site. He reported the technical details very quick. Thank you!
    14 August, 2018
     PaulDowding10 Paul from Connectix:
Many thanks to Andre for providing a quick and professional service. Our XSS vulnerability was identified and patched within 24 hours. Excellent!
    9 August, 2018
     b4tius dmitri from autoklad:
Thanks to Andre for helping to fix XSS vulnerability
    30 July, 2018
     fotoloco1 Blaise from fotoloco:
Excellent report: I was easily able to patch the security vulnerability with Andre's report. Thanks!
    18 July, 2018
     0xBashCat Basil from Noneya Business:
Andre responsibly disclosed and helped us to patch a XSS vulnerability on several production websites. He was very professional with his communications, and we're very thankful for his help. Sending a swag bag overseas ended up being more complicated than expected. But Andre seems to be a great guy, and we want to show our appreciation in every way we can. Thank you, Andre!
    13 July, 2018
     tnyaritm Tamás from Mediashop CEE:
Andre help us to find and fix XSS issue on our webshop!
Thank you for your help Andre!
    5 July, 2018
     SandiSchleicher SSchleicher from iConsumer:
Andre notified us about an XSS issue which has been fixed thanks to his help. We appreciate your help Andre!
    20 June, 2018
     teamhively Julian from Hively:
Thanks Andre for picking up an issue for us and for the prompt, friendly communication on the issue.
    15 June, 2018
     eJumpMedia Bogdan from eJump Media:
Thanks to Andre who found a vulnerability on a website I developed, I was able to fix it ASAP without any complications. His feedback was quick and accurate, with an open and nice attitude towards me. I strongly recommend Andre for anyone who faces security issues or anything related!
    14 June, 2018
     luziczek Maciek from
Thanks to Andre for finding and reporting XSS vulnerability which has been fixed.
    12 June, 2018
     JoshHar25910089 Josh from ABA:
Thanks for finding the XSS vulnerability - very helpful, and he was quick to respond when I couldn't reproduce it.
    11 June, 2018
     GlamiBackstage Ondřej Čech from Glami:
Thank you Andre for spotting an XSS exploit - We appreciated the feedback and information to help us resolve the issue promptly!
    11 June, 2018
     wladiolo Paolo from Fastweb:
Thanks Andre for your responsible disclosure, it was very appreciated and useful.
    30 May, 2018
     SandiSchleicher SSchleicher from iConsumer:
Thanks for reporting the issue Andre. We always appreciate help to improve our service.
    21 May, 2018
     Printerous1 Ivan from Printerous:
Thank you for notifying us about security hole in our old website.
We didn't notice that there is a piece of old unused code that is still open to XSS breach.
    21 May, 2018
     FalikSh55583121 Falik Sher from TruConversion:
Thank you Andre for reporting the problem. Now the vulnerability has been fixed.
Much appreciated.
    3 May, 2018
     Printerous1 Ivan from Printerous:
Andre helped us very quickly and clearly. I am very thankful for his good will and reporting in a responsible manner.
    23 April, 2018
     jcopley Joe Copley from
Andre was very helpful in identifying and resolving a vulnerability on our site. Many thanks!!
    16 April, 2018
     fourhundredkg 400kg from aim400kg:
Thanks for report about cookie hole on my site :)
    10 March, 2018
     dmholtof Don Holtof from Totally Fuzzzy:
Thanks to login_denied for the finding and reporting of the XSS vulnerability. All fixed now. Much appreciated.
    8 March, 2018
     777livecams Jan from 777 Systems:
Andre gave us detailed information about a vulnerability. Thank you very much!
    6 March, 2018
     tobyweston ELA from ELA:
Thanks to Andre for spotting an XSS exploit - We appreciated the feedback and information to help us resolve the issue promptly!
    3 March, 2018
     ZonaZeroNet Ramon from ZonaZero: