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610,843 coordinated disclosures
392,918 fixed vulnerabilities
926 bug bounties with 1,856 websites
18,793 researchers, 1199 honor badges

Tech4 | Security Researcher Profile


Security researcher Tech4 has already helped fix 64 vulnerabilities.



Researcher reputation:  40

Real name:
Yuji Hayamizu

About me:
SOC Analyst from Japan

How to contact me:
tech{AT}4{DOT}zaq{DOT}jp

All communications will be kept private.

Award / Bug Bounty I prefer:
A thanks/profile recommendation is enough, but if you feel like treating me to something extra I appreciate the following -

Bug Bounty
Vouchers (eg. Amazon)
Gadgets
Swag
Hall of Fame

Follow me on:
Twitter

Recommendations and Acknowledgements

@h_ono     3 August, 2020
    Twitter h_ono h_ono from DBCLS:
Great work, thanks for finding a bug and kindly reporting it.
@juunkwan     17 February, 2020
    Twitter juunkwan Jun Takashima from AID-DCC:
Thank you for your polite response.
It was very helpful.

Please login via Twitter to add a recommendation

Honor Badges


Number of Secured Websites

10+ Secured Websites Badge
50+ Secured Websites Badge
500+ Secured Websites Badge
Web Security Veteran Badge
10+ Websites
50+ Websites
500+ Websites
WEB SECURITY VETERAN
1000+ Websites

Advanced Security Research

WAF Bypasser Badge
CSRF Master Badge
AppSec Logic Master Badge
Fastest Fix Badge
WAF Bypasser
CSRF Master
30+ Reports
AppSec Logic Master
30+ Reports
Fastest Fix
Fix in 24 hours

Outstanding Achievements

Secured OBB Badge
OBB Advocate Badge
Improved OBB Badge
Secured OBB
OBB Advocate
Improved OBB

Commitment to Remediate and Patch

Patch Master Badge
Patch Guru Badge
Patch Lord Badge
Patch Master
55% Patched
Patch Guru
65% Patched
Patch Lord
75% Patched

Recommendations and Recognition

REPUTABLE Badge
FAMOUS Badge
GLOBALLY TRUSTED Badge
REPUTABLE
10+ Recommends
FAMOUS
25+ Recommends
GLOBALLY TRUSTED
50+ Recommends

Distinguished Blog Author

Distinguished Blog Author Badge
Distinguished Blog Author Badge
Distinguished Blog Author Badge
1 Post
3 Posts
5+ Posts

Research Statistics



Total reports:148
Total reports on VIP sites:7
Total patched vulnerabilities:64
Total vulnerabilities on Hold (Open Bug Bounty):5
Recommendations received:2
Active since:02.02.2020

Open Bug Bounty Certificate


Researcher Certificate



No posts in blog yet


Reported Vulnerabilities

All Submissions VIP Submissions

Domain Reported Status Type
27.08.2020
On Hold
Cross Site Scripting
27.08.2020
patched
Cross Site Scripting
25.08.2020
On Hold
Cross Site Scripting
23.08.2020
On Hold
Cross Site Scripting
22.08.2020
On Hold
Cross Site Scripting
15.08.2020
patched
Cross Site Scripting
10.08.2020
patched
Cross Site Scripting
10.08.2020
patched
Cross Site Scripting
05.08.2020
patched
Cross Site Scripting
01.08.2020
patched
Cross Site Scripting
25.07.2020
unpatched
Open Redirect
25.07.2020
patched
Cross Site Scripting
24.07.2020
patched
Improper Access Control 
19.07.2020
patched
Cross Site Scripting
05.07.2020
patched
Cross Site Scripting
05.07.2020
unpatched
Cross Site Scripting
05.07.2020
patched
Cross Site Scripting
01.07.2020
patched
Cross Site Scripting
01.07.2020
patched
Cross Site Scripting
01.07.2020
patched
Cross Site Scripting

  Latest Patched

 29.10.2020 skin.gs
 28.10.2020 plos.org
 28.10.2020 audiusa.com
 28.10.2020 um.es
 28.10.2020 bpjs-kesehatan.go.id
 28.10.2020 dooda.me
 28.10.2020 inews.id
 28.10.2020 faz.net
 27.10.2020 dek-d.com
 27.10.2020 dict.cc

  Latest Blog Posts

26.10.2020 by _r00t1ng_
Bypass Addslashes using Multibyte Character
26.10.2020 by _r00t1ng_
One Payload to Inject them all - MultiQuery Injection
26.10.2020 by _r00t1ng_
Routed SQL Injection
26.10.2020 by _r00t1ng_
DIOS the SQL Injectors Weapon
26.10.2020 by p4c3n0g3
How to find AngularJS XSS

  Recent Recommendations

@MizoueShumpei     29 October, 2020
    Twitter MizoueShumpei:
Thank you very much for your help.
@adridder     28 October, 2020
    Twitter adridder:
Thank you for your help with this XSS vulnerability on our site. We appreciate the responsible reporting via openbugbounty.
@gaborvitez     28 October, 2020
    Twitter gaborvitez:
Ajaysen R found a reflected cross site scripting bug in one of our cgi scripts, this way he helped us improve the security of our website. He was really fast to react, working with him was really a pleasure. We are grateful for the issues he made us aware of.
@Jobe1986     28 October, 2020
    Twitter Jobe1986:
Thank you for your efforts and reporting the XSS vulnerability you found on my website.
@TConfetti     28 October, 2020
    Twitter TConfetti:
Vighnesh Gupta was responsive and professional in helping us remediate a bug on our website. Thank you for your insight, Vighnesh.