Web challenges
Reach data or functionality the application meant to keep from you - through its inputs, its tokens, or its trust in the client.
3,186 in the index. The 200 below are ranked by how many independent published solutions exist - which is the right order for learning, not for difficulty. A challenge with nine writeups gives you nine explanations of the same technique to compare; a harder one nobody documented gives you none.
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Takoma Park CTF 2017363 writeupsldab
CSAW CTF Qualification Round 2018 201815 writeupsproducts manager
Facebook CTF 2019 201913 writeupsKryptos Support
Cyber Apocalypse CTF 2022: Intergalactic Chase 202211 writeupsRobots
RITSEC CTF 2021 202111 writeupsorange v1
CSAW CTF Qualification Round 2017 201711 writeupscrahp
Nullcon Goa HackIM 2025 CTF 202510 writeupsBabier CSP
DiceCTF 2021 202110 writeupsCAAS
Cyber Apocalypse 2021 202110 writeupsHermit - Part 1
UMassCTF 2021 202110 writeupsSimple web
DCTF 2021 202110 writeupsSpooky Store
UTCTF 2020 202010 writeupsLogin App
TAMUctf 19 201910 writeupsmisdirection
RITSEC CTF 2019 201910 writeupsRobots Rule
TAMUctf 19 201910 writeupsBaby PHP
Hack.lu CTF 2018 201810 writeupsSimpleAuth
TokyoWesterns CTF 4th 2018 201810 writeupsBotBot
BITSCTF 2017 201710 writeupssmartcat1
Insomni'hack teaser 2016 201610 writeupsWeb 80 - 0ldsk00lBlog
Internetwache CTF 2016 201610 writeupsWeb 400
CSAW CTF Qualification Round 2013 201310 writeupsBlinker Fluids
Cyber Apocalypse CTF 2022: Intergalactic Chase 20229 writeupsMutation Lab
Cyber Apocalypse CTF 2022: Intergalactic Chase 20229 writeupsminiSTRypalace
Cyber Apocalypse 2021 20219 writeupsToy Workshop
Cyber Santa is Coming to Town 20219 writeupsLeak audit
Syskron Security CTF 2020 20209 writeupspanda-facts
redpwnCTF 2020 20209 writeupspasteurize
Google Capture The Flag 2020 20209 writeupsQR Generator
Houseplant CTF 2020 20209 writeupsBuckets of fun
RITSEC CTF 2019 20199 writeupsMy admin panel
CONFidence CTF 2019 Teaser 20199 writeupsOur First API
RITSEC CTF 2019 20199 writeupsScience!
TAMUctf 19 20199 writeupsSecure-Coding-Science!
TAMUctf 19 20199 writeupsJS Safe 2.0
Google Capture The Flag 2018 (Quals) 20189 writeupssso
CSAW CTF Qualification Round 2018 20189 writeupsVulnShop
Insomni'hack teaser 2018 20189 writeupsBatman vs Joker
BITSCTF 2017 20179 writeupsSharePoint
VolgaCTF 2017 Quals 20179 writeupssmartcat2
Insomni'hack teaser 2016 20169 writeupsSpotlight
IceCTF 2016 20169 writeupsnumberizer
Nullcon Goa HackIM 2025 CTF 20258 writeupsTemptation
Nullcon Goa HackIM 2025 CTF 20258 writeupsZONEy
Nullcon Goa HackIM 2025 CTF 20258 writeupsterms-and-conditions
LA CTF 2024 20248 writeupsDababy
RITSEC CTF 2021 20218 writeupsE.Tree
Cyber Apocalypse 2021 20218 writeupsSea of Quills
ångstromCTF 2021 20218 writeupsToy Management
Cyber Santa is Coming to Town 20218 writeupsunder Development
S.H.E.L.L. CTF 20218 writeupsWild Goose Hunt
Cyber Apocalypse 2021 20218 writeupsstatic-pastebin
redpwnCTF 2020 20208 writeupsBird Box Challenge
TAMUctf 19 20198 writeupsBuckets
TAMUctf 19 20198 writeupsBeliever Case
HackIT CTF 2018 20188 writeupsLights Out!
IceCTF 2018 20188 writeupsphp
35C3 CTF 20188 writeupsThe Most Secure File Uploader
InCTF 2018 20188 writeupseasyauth
BSides San Francisco CTF 20178 writeupsEcho
PlaidCTF 2017 20178 writeupssmarttomcat
Insomni'hack teaser 2017 20178 writeupsWeb 90 - TexMaker
Internetwache CTF 2016 20168 writeupsPaginator
Nullcon Goa HackIM 2025 CTF 20257 writeupsPaginator v2
Nullcon Goa HackIM 2025 CTF 20257 writeupssess.io
Nullcon Goa HackIM 2025 CTF 20257 writeupsOrbital
Cyber Apocalypse 2023: The Cursed Mission 20237 writeupsPassman
Cyber Apocalypse 2023: The Cursed Mission 20237 writeupsknock-knock
DiceCTF 2022 20227 writeupsSymple Unzipper
justCTF 2022 20227 writeupsBuild-a-website
ImaginaryCTF 2021 20217 writeupsElf Directory
Cyber Santa is Coming to Town 20217 writeupsGadget Santa
Cyber Santa is Coming to Town 20217 writeupsHermit - Part 2
UMassCTF 2021 20217 writeupsMissing Flavortext
DiceCTF 2021 20217 writeupsPwnQL #1
HeroCTF v3 20217 writeupsVery Secure Website
DCTF 2021 20217 writeupsautograder
WPICTF 2020 20207 writeupsBlog from the future
Houseplant CTF 2020 20207 writeupsEpic Admin Pwn
UTCTF 2020 20207 writeupsFile Viewer
TJCTF 2020 20207 writeupsGit Good
ångstromCTF 2020 20207 writeupsI don't like needles
Houseplant CTF 2020 20207 writeupsLocalghost
NahamCon CTF 20207 writeupslogin
redpwnCTF 2020 20207 writeupsNetcorp
VolgaCTF 2020 Qualifier 20207 writeupsNo Sleep
riceteacatpanda 20207 writeupsSecurity headers
Syskron Security CTF 2020 20207 writeupsTracking
DawgCTF 2020 20207 writeupsUwu?
riceteacatpanda 20207 writeupsWhat's in the box?
riceteacatpanda 20207 writeupsWoooosh
ångstromCTF 2020 20207 writeupsXmas Still Stands
ångstromCTF 2020 20207 writeupsAgent Keith
HSCTF 6 20197 writeupscant_even_unplug_it
DEF CON CTF Qualifier 2019 20197 writeupsfile magician
hxp 36C3 CTF 20197 writeupsmd5--
HSCTF 6 20197 writeupsNetworked Password
HSCTF 6 20197 writeupsNo Sequels
ångstromCTF 2019 20197 writeupsNot Another SQLi Challenge
TAMUctf 19 20197 writeupsRoboworld
X-MAS CTF 2019 20197 writeupsSecure System
TetCTF 2020 20197 writeupsSequel Fun
X-MAS CTF 2019 20197 writeupsWrestlerBook
SunshineCTF 2019 20197 writeupsCrimemail
INS'hAck 2018 20187 writeupsJuniorCTF - flags
35C3 CTF 20187 writeupsShrine
TokyoWesterns CTF 4th 2018 20187 writeupsToke relaunch
IceCTF 2018 20187 writeupswho knows john dows?
Hackover CTF 2018 20187 writeupsPrudentialv2
Boston Key Party CTF 2017 20177 writeupsPykemon
PlaidCTF 2017 20177 writeupsWeb1
nullcon HackIM 20177 writeupszumbo1
BSides San Francisco CTF 20177 writeupsChainedIn
IceCTF 2016 20167 writeupsExposed
IceCTF 2016 20167 writeupsGeocities
IceCTF 2016 20167 writeupsGlobal Page
Tokyo Westerns/MMA CTF 2nd 2016 20167 writeupsMove Along
IceCTF 2016 20167 writeupsToke
IceCTF 2016 20167 writeupsWeb 60 - Replace with Grace
Internetwache CTF 2016 20167 writeupsLawn Care Simulator
CSAW CTF Qualification Round 2015 20157 writeupssecure web
SECUINSIDE CTF Quals 2013 20137 writeupsbfail
Nullcon Goa HackIM 2025 CTF 20256 writeupsFree Flag
BlackHat MEA CTF Qualification 2024 20246 writeupsWhat's My Password?
IrisCTF 2024 20246 writeupsBottle Poem
SekaiCTF 2022 20226 writeupsFlag in Space
Space Heroes 2022 20226 writeups0xSSRF
HeroCTF v3 20216 writeupsAll A-Loan
DEADFACE CTF 20216 writeupsBlitzProp
Cyber Apocalypse 2021 20216 writeupsCareers
Intent CTF 2021 20216 writeupsHackme
0x41414141 CTF 20216 writeupsheim
UMassCTF 2021 20216 writeupsIllusion
Pwn2Win CTF 2021 20216 writeupsIndead v1
HackPack CTF 2021 20216 writeupsInspector Gadget
Cyber Apocalypse 2021 20216 writeupsJar
ångstromCTF 2021 20216 writeupslogin
S.H.E.L.L. CTF 20216 writeupsPhonetic
H@cktivityCon 2021 CTF 20216 writeupssecure
redpwnCTF 2021 20216 writeupsSpoofy
ångstromCTF 2021 20216 writeupsThe Matrix
UMDCTF 2021 20216 writeupsThese Ladies Paved Your Way
DawgCTF 2021 20216 writeups??? (zoop mail)
WPICTF 2020 20206 writeupsAgent 95
NahamCon CTF 20206 writeupsBite
HacktivityCon CTF 20206 writeupsConsolation
ångstromCTF 2020 20206 writeupsFilestorage
TAMUctf 2020 20206 writeupsFlag Jokes
NahamCon CTF 20206 writeupsGif2png
CyBRICS CTF 2020 20206 writeupslog-me-in
Google Capture The Flag 2020 20206 writeupsMissing Image
Newark Academy CTF 2020 20206 writeupsPassword Extraction
TAMUctf 2020 20206 writeupsPhishing for Flags
riceteacatpanda 20206 writeupsPHP İnformation
DarkCTF 20206 writeupsPrograms Only
b01lers CTF bootcamp 20206 writeupsReindeer Flotilla
b01lers CTF bootcamp 20206 writeupsRobots. Yeah, I know, pretty obvious
riceteacatpanda 20206 writeupssecrent agents
ångstromCTF 2020 20206 writeupsSelfhost all the things!
Houseplant CTF 2020 20206 writeupsTemplate Shack
HacktivityCon CTF 20206 writeupstux-fanpage
redpwnCTF 2020 20206 writeupsWeb Warm-up
ASIS CTF Quals 2020 20206 writeupswidthless
CSAW CTF Qualification Round 2020 20206 writeups1337 Secur1ty
TAMUctf 19 20196 writeupsCookie Monster
Pragyan CTF 2019 20196 writeupsgetaflag
WPICTF 2019 20196 writeupsGovernment Agriculture Network
Google Capture The Flag 2019 (Quals) 20196 writeupsKeith Logger
HSCTF 6 20196 writeupsMandatory PHP
Pragyan CTF 2019 20196 writeupsMany Gig'ems to you!
TAMUctf 19 20196 writeupsunagi
CSAW CTF Qualification Round 2019 20196 writeupsWrestler Name Generator
SunshineCTF 2019 20196 writeupsCat Chat
Google Capture The Flag 2018 (Quals) 20186 writeupshiddenDOM
noxCTF 2018 20186 writeupsLazy Dev
RITSEC CTF 2018 20186 writeupsOmegaSector
Meepwn CTF Quals 2018 20186 writeupsPixEditor
Nuit du Hack CTF Quals 2018 20186 writeupsSpecial Force
RITSEC CTF 2018 20186 writeupsThe Tangled Web
RITSEC CTF 2018 20186 writeupsThe Vault
SwampCTF 2018 20186 writeupsUnfinished business
Pragyan CTF 2018 20186 writeupsWhat a cute dog!
RITSEC CTF 2018 20186 writeupsBon Appétit
SHA2017 CTF 20176 writeupsDig Dug
ASIS CTF Finals 2017 20176 writeupsGit Gud
TUCTF 2017 20176 writeupsGolem is stupid!
ASIS CTF Finals 2017 20176 writeupsNaughty ads
SEC-T CTF 20176 writeupsSqlSRF
SECCON 2017 Online CTF 20176 writeupsTHE-WALL
BackdoorCTF 2017 20176 writeupsWeb2
nullcon HackIM 20176 writeupszumbo2
BSides San Francisco CTF 20176 writeupsErnst Echidna
Google Capture The Flag 2016 20166 writeupsGood Morning
Boston Key Party CTF 2016 20166 writeupsKitty
IceCTF 2016 20166 writeupsSpotted Quoll
Google Capture The Flag 2016 20166 writeupsWho's a good boy
RC3 CTF 2016 20166 writeupsHidden flag
ASIS CTF Quals 2014 20146 writeupsPay TV
Hack.lu CTF 2013 20136 writeupssecure web revenge
SECUINSIDE CTF Quals 2013 20136 writeupsPasty
Nullcon Goa HackIM 2026 CTF 20265 writeups
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