Cybersecurity servers

150 measured server(s) with the Cybersecurity sub-topic, ranked by real members. Browse topics →

Server	Members	Online	Active
1 Kali Linux & Friends	72,738	3,958	5.4%
2 TECH HAUS	17,396	1,666	9.6%
3 ImaginaryCTF	14,120	1,517	10.7%
4 CTFlearn	11,986	737	6.1%
5 CryptoHack	10,750	1,306	12.1%
6 AI Security Engineers	9,836	848	8.6%
7 THE NEMICO NETWORK📡	7,798	922	11.8%
8 SECCON Beginners CTF	6,723	637	9.5%
9 Hackless 🥷	6,555	39	0.6%
10 SkillBit (formerly MetaCTF)	6,172	963	15.6%
11 FCSC & Hackropole	6,059	898	14.8%
12 Parrot Security	5,899	529	9.0%
13 Practical Networking	5,486	260	4.7%
14 GoogleCTF	5,448	877	16.1%
15 HITCON CTF	5,387	924	17.2%
16 SekaiCTF 2026	5,146	988	19.2%
17 404 CTF	4,521	870	19.2%
18 Digital Forensics	3,970	745	18.8%
19 ångstromCTF	3,933	337	8.6%
20 VishwaCTF	3,919	126	3.2%
21 Real World CTF	3,713	264	7.1%
22 UIUCTF 2026	3,667	637	17.4%
23 SunshineCTF	3,594	570	15.9%
24 Midnight Sun CTF	3,573	693	19.4%
25 nullcon HackIM 2026	3,455	150	4.3%
26 ASIS CTF	3,417	564	16.5%
27 UTCTF 2026	3,373	344	10.2%
28 InfoSec VPN	3,360	45	1.3%
29 Deep Hat	3,352	271	8.1%
30 PatriotCTF 2026	3,337	645	19.3%
31 scriptCTF	3,230	324	10.0%
32 idekCTF	3,178	315	9.9%
33 Techies Hideaway	3,178	513	16.1%
34 247CTF	3,141	222	7.1%
35 b01lersCTF	3,085	325	10.5%
36 BlueCapeSecurity	3,042	195	6.4%
37 UMassCTF 2026	3,024	332	11.0%
38 BuckeyeCTF 2025	2,901	503	17.3%
39 WormGPT Official	2,895	116	4.0%
40 DEADFACE CTF	2,850	602	21.1%
41 Dex Security	2,728	137	5.0%
42 corCTF	2,711	524	19.3%
43 KalmarCTF	2,705	523	19.3%
44 Kaspersky{CTF}	2,686	179	6.7%
45 Official HackMyVM	2,650	174	6.6%
46 HSCTF	2,616	174	6.7%
47 CrewCTF 2025	2,582	269	10.4%
48 KnightCTF	2,561	196	7.7%
49 TSG CTF	2,521	227	9.0%
50 smileyCTF 2025	2,472	288	11.7%
51 Hack.lu CTF	2,470	263	10.6%
52 XCTF 10th–SCTF 2026	2,426	112	4.6%
53 niteCTF '25	2,406	149	6.2%
54 GPN CTF 2026	2,398	334	13.9%
55 rCTF	2,381	184	7.7%
56 Midnight Flag CTF - EXECUTION	2,327	323	13.9%
57 DIVER OSINT CTF	2,318	266	11.5%
58 CISO Assistant - GRC community	2,277	168	7.4%
59 HACKTORIA	2,239	255	11.4%
60 R3CTF 2026	2,170	327	15.1%
61 NNS CTF	2,097	323	15.4%
62 b01lers	2,083	351	16.9%
63 1753CTF	2,079	217	10.4%
64 Rhino Security Labs	2,043	204	10.0%
65 Dev Universe - FGTE CTF	1,921	110	5.7%
66 UMDCTF 2026	1,909	266	13.9%
67 HackDay	1,899	130	6.8%
68 SECCON CTF 14	1,879	283	15.1%
69 BCACTF	1,853	204	11.0%
70 CTF@CIT	1,847	171	9.3%
71 JerseyCTF 🔒	1,830	265	14.5%
72 Cyber Odyssey: Akasec CTF	1,783	101	5.7%
73 InCTF Nationals	1,777	48	2.7%
74 zer0pts CTF	1,758	183	10.4%
75 jailCTF 2026	1,749	214	12.2%
76 N0PSctf	1,726	200	11.6%
77 SECCON CTF 13	1,709	229	13.4%
78 Maltego Community OSINT	1,686	97	5.8%
79 IrisCTF	1,675	192	11.5%
80 BlahajCTF	1,634	98	6.0%
81 pwnable.tw	1,505	156	10.4%
82 DamCTF	1,504	185	12.3%
83 xCTFs	1,470	273	18.6%
84 TetCTF	1,421	130	9.1%
85 CyberDawgs Club	1,411	162	11.5%
86 TAMUctf 2026	1,391	183	13.2%
87 ECW CTF	1,391	206	14.8%
88 RITSEC CTF	1,373	250	18.2%
89 SECCON CTF 2023	1,350	160	11.9%
90 FAUST CTF 2026	1,337	263	19.7%
91 Arqora	1,302	127	9.8%
92 BSides Tampa	1,301	194	14.9%
93 @Hack CTF - Concordia	1,294	167	12.9%
94 Sieberrsec CTF	1,294	124	9.6%
95 SpookyCTF	1,279	185	14.5%
96 CyberSpace CTF 2024	1,273	127	10.0%
97 CakeCTF 2023	1,259	125	9.9%
98 hackerspace - DropCTF	1,243	78	6.3%
99 ISITDTU-CTF	1,240	93	7.5%
100 Hack In The North	1,240	12	1.0%
101 AlpacaHack	1,232	181	14.7%
102 UnitedCTF	1,212	251	20.7%
103 WaniCTF	1,209	159	13.2%
104 ELORIA	1,184	53	4.5%
105 wpictf	1,145	42	3.7%
106 DaVinciCTF	1,139	78	6.8%
107 HKCERT CTF 2024	1,117	92	8.2%
108 RingZer0 CTF	1,113	179	16.1%
109 pingCTF 2026	1,104	132	12.0%
110 Shutlock CTF 🕵	1,101	230	20.9%
111 NCKUCTF	1,096	317	28.9%
112 SaaS Alerts	1,091	172	15.8%
113 BDSec CTF	1,079	60	5.6%
114 DFIR-IRIS	1,066	102	9.6%
115 Swiss Hacking Challenge	1,059	124	11.7%
116 Paradigm CTF	1,046	107	10.2%
117 BSides Atlanta	1,037	146	14.1%
118 x3CTF 2026	1,029	196	19.0%
119 squ1rrel CTF 2026	1,028	103	10.0%
120 RACTF	1,017	63	6.2%
121 Olympics CTF	996	72	7.2%
122 PearlCTF	988	58	5.9%
123 Pragyan CTF'26	978	54	5.5%
124 IRON CTF 2024	977	54	5.5%
125 pwnable.kr	954	111	11.6%
126 HTB Meetups Mexico	948	58	6.1%
127 CISSP・CBKを中心としたセキュリティ学習WG	946	58	6.1%
128 SwampCTF	943	96	10.2%
129 Arab & Africa Regional CTF	936	27	2.9%
130 Break the Syntax CTF	934	115	12.3%
131 P3rf3ctr00t CTF	896	47	5.2%
132 DEF CON Group Trivandrum	894	21	2.3%
133 Wargames.MY CTF 2024	884	40	4.5%
134 BRICS+ CTF	882	80	9.1%
135 pwntools	881	134	15.2%
136 NewbieContest	872	52	6.0%
137 Wizer CTF	804	35	4.4%
138 DAMSEC CTF LEAGUE	797	140	17.6%
139 Cryptocracy™	790	28	3.5%
140 EnigmaXplore 3.0	771	33	4.3%
141 snakeCTF	766	120	15.7%
142 HACK'OSINT - CTF	760	138	18.2%
143 07CTF	735	64	8.7%
144 BH CTF	730	71	9.7%
145 TSCCTF 2026	709	163	23.0%
146 PolyU NuttyShell CTF Competition	702	75	10.7%
147 San Diego CTF 2022	690	44	6.4%
148 Cyber Ninja CTF by OTERIA	684	45	6.6%
149 Crate-CTF	684	151	22.1%
150 Uni Bonn Community CTF	680	122	17.9%