| H00die | H00die-gr3y | H07 |
| H0ng10 | H0tTurk- | H3rcul3s |
| H3v0x | H4ck3r#47 | H4ckCity Security Team |
| H4cky | H4cky0u | H4ntu |
| H4rk3nz0 | H4shur | H4x0r-dz |
| H4xorcrew | H4 / XPK | Haamed Gheibi |
| Haboob Team | Hacefresko | HaCk-13 TeaM |
| Hack2prison | Hack4love | Hack 912 |
| HACKATTACK | HACKATTACK IT SECURITY GmbH | Hackberry |
| Hackerbinhphuoc | Hacker CooL | HaCkeR EgY |
| Hacker Fantastic | Hackerlounge Research Group | Hackers Center Security |
| HACKERS PAL | Hacker@sr.gov.yu | Hacking Expose! |
| Hackk.gr | Hackologie | HackXBack |
| Hadihadi | Hadi Kiamarsi | Hadi Mene |
| Hadji Samir | Haggis | Haider Mahmood |
| Haifei Li | HaiHui | Haiku Hacker |
| Hai Nam Luke | Hak3r-b0y | Hakxer |
| Halfdog | Halil Dalabasmaz | Halim Cruzito |
| Halkfild | Haluznik | Hamdi Sevben |
| Hamed Bazargani | Hamid Ebadi | Hamid Zamani |
| Hamit CIBO | Hamit CİBO | HaMM0nz |
| Hamtaro | Hamza Khedr | Hamza Megahed |
| Hamza 'MizoZ' N. | Handle Nopman | Handrix |
| Hank Leininger | Hanley Shun | Hannes Trunde |
| Hannibal Lector | Hanno Bock | Hanno Boeck |
| HanowarS | Han Sahin | Hans Jerry Illikainen |
| Hans-Martin Muench | Hans Topo & G0tmi1k | Hantwister |
| Harikiri | Harish Ramadoss | Harom Ramos |
| Haroon Meer & Roelof Temmingh | Haroon Rashid Astwat | Harrison Neal |
| Harry | Harry Metcalfe | Harry Sintonen |
| Harsha Bhat | Harshit | Harshit Joshi |
| Harun Karakis | Hasadya Raed | Hasan Alqawzai |
| Hash3liZer | Hashim Jawad | HashoR |
| Hassy Vinod Eshan | Hat-Squad Security Team | HauntIT |
| Havenard | Hayden Wright | Hay Mizrachi |
| Haypo | Hazem Mofeed | HaZl0oh |
| Hc0 | Hd1979 | Hdarwin |
| Hdlkha | Hdm | HeadlessZeke |
| Hector Marco | Hector Marco & Ismael Ripoll | Hector Monsegur |
| Hector X. Monsegur | Heine Pedersen | Heiner Liesegang |
| Heise Security | Heka | Heliand Dema |
| Hello@iwamot.com | Hellok | Helmut Grohne |
| Helmuth Antholzer | Help AG Middle East | Hemant Kashyap |
| Hempel | Henrik Pedersen | Henri Lindberg |
| Henrique Montenegro | Henri Salo | Henry Hoggard |
| HER0 | Herbert Xu | HerculesRD |
| Heretic2 | Hernan Ochoa | Hessam-x |
| Heurs | Hever Costa Rocha | HEX |
| Hex0r | Hex 26 | HexView |
| Heyder Andrade | Hfiref0x | Hhjj |
| Hidayat Sagita | High-Tech Bridge | High-Tech Bridge SA |
| Hillary Benson | Himanshu Mehta | Himeur Nourredine |
| Hinge | Hip | Hiphop |
| Hiromitsu Takagi | Hiroshi Shimamoto | His0k4 |
| Hisato Killing | HIva Team | HJauditing Employee Tim |
| Hkm | Hkpco | HLL |
| HNK Technology Solutions | Hoang Yen | Hobbily Plunt |
| Hodorsec | HolyGhost | Hong10 |
| Hong Nhat Pham | Hongzhen Zhou | Honoriak |
| Hood3dRob1n | Hook-s3c | Horoszkiewicz Julian ISP |
| Horst Schirmeier | Hosein Askari | Hosein Vita |
| Hossein Hezami | Hossein Lotfi | Houjingyi |
| Houseofdabus | Houssamix | Howard M. Kash III |
| Hoyt LLC Research | Hritik Vijay | H-Security Labs |
| Hsj | H-SK33PY | H!tm@N |
| HTP | HTrovao | H-T Team |
| Http-equiv | Huang Anwen | Hubert Gradek |
| Hugh Mann | Hugo Breton | Hugo Caye |
| Hugo Santiago | Hugo Vazquez | Humberto |
| Humberto J. Abdelnur | Humblelad | Hunger |
| HuoFu | Hurley | Huseein Amer |
| Husinul Sanub | Hussin X | HuXfLuX |
| Huy Kha | Huy-Ngoc DAU | Huzaifa Hussain |
| Huzaifa Sidhpurwala | HvM17 | HxH |
| Hyp3rlinx | Hypoclear | Hzllaga |
Vulmon