UIUCTF 2020 Writeups



For UIUCTF 2020 we paid out $1,600 in writeup prizes. We were inspired by GoogleCTF’s writeup prizes. We prioritize concise technical communication and writeups that are fun to read and learn from, including those written from/for the perspective of beginners. Here are the writeups that won.

Challenge Author
MuJS ptr-yudai - zer0pts
MuJS pepsipu - DiceGang
MuJS M30W - DiceGang
Accounting Accidents ptr-yudai - zer0pts
Accounting Accidents M30W - DiceGang
Accounting Accidents notreally - IrisSec
Accounting Accidents fanpu - PPP
Bot Protection IV nanase - Black Bauhinia
Bot Protection IV whysw - MINUS
Bot Protection IV infuzion - infuzion
Bot Protection IV DiceGang - DiceGang
CalATMity notreally - IrisSec
CalATMity defund - DiceGang
Crazy_Caches D4nch3n - HTCPCP://
Et Tu Blathers? GeoffreyY - Black Bauhinia
Et Tu Blathers? adbforlife - PPP
Feedback Survey JC01010 - /[spin]*s/
Feedback Survey willwam845 - wiwam845
Feedback Survey matdaneth - [sqrt(-1) + 1]
Feedback Survey willwam845 - wiwam845
Freaky_File_Descriptors ptr-yudai - zer0pts
Freaky_File_Descriptors D4nch3n - HTCPCP://
Freaky_File_Descriptors meow - DiceGang
Freaky_File_Descriptors trinary-exploitation - 3PAC
Friendship Gone Awry DiceGang (shared account) - DiceGang
Gen Z Math Class clam - DiceGang
How to Get Started matdaneth - [sqrt(-1) + 1]
Isabelle’s Bad Opsec 1 hulkhogan - Fairy Sector
Isabelle’s Bad Opsec 1 matdaneth - [sqrt(-1) + 1]
Isabelle’s Bad Opsec 1 skat - IrisSec
Isabelle’s Bad Opsec 2 hulkhogan - Fairy Sector
Isabelle’s Bad Opsec 2 matdaneth - [sqrt(-1) + 1]
Isabelle’s Bad Opsec 2 skat - IrisSec
Isabelle’s Bad Opsec 3 hulkhogan - Fairy Sector
Isabelle’s Bad Opsec 3 matdaneth - [sqrt(-1) + 1]
Isabelle’s Bad Opsec 3 skat - IrisSec
Isabelle’s Bad Opsec 4 hulkhogan - Fairy Sector
Isabelle’s Bad Opsec 4 matdaneth - [sqrt(-1) + 1]
Isabelle’s Bad Opsec 4 Odious - 4dumbsters
Isabelle’s Bad Opsec 4 skat - IrisSec
Isabelle’s Bad Opsec 5 hulkhogan - Fairy Sector
Isabelle’s Bad Opsec 5 matdaneth - [sqrt(-1) + 1]
Isabelle’s Bad Opsec 5 skat - IrisSec
Just a Normal CTF Quintec - RGBsec
Just a Normal CTF matdaneth - [sqrt(-1) + 1]
Just a Normal CTF Odious - 4dumbsters
K.K’s Mixtape ranguli - Group 3
K.K’s Mixtape matdaneth - [sqrt(-1) + 1]
KASLR_Leak ptr-yudai - zer0pts
KASLR_Leak D4nch3n - HTCPCP://
Kernel Showcase ptr-yudai - zer0pts
Kernel::Run_it_as_Root D4nch3n - HTCPCP://
Kernel::Run_it_as_Root trinary-exploitation - 3PAC
Kernel::Time_To_Start ptr-yudai - zer0pts
Kernel::Time_To_Start Lone person that played I think. :D - JHDiscord
Kernel::Time_To_Start alicelambda - alicelambda
Kernel::Time_To_Start matdaneth - [sqrt(-1) + 1]
Kernel::Time_To_Start D4nch3n - HTCPCP://
Kernel::Time_To_Start Fane - OpenToAll
Kernel::Time_To_Start Odious - 4dumbsters
Kernel_Memory_Leak Lone person that played I think. :D - JHDiscord
Kernel_Memory_Leak Fane - OpenToAll
Omega Stonks Quintec - RGBsec
Omega Stonks JC01010 - /[spin]*s/
Omega Stonks matdaneth - [sqrt(-1) + 1]
Oops D4nch3n - HTCPCP://
RFCland ptr-yudai - zer0pts
RFCland signified - KGB_sec
RFCland notreally - IrisSec
Raymonds Recovery matdaneth - [sqrt(-1) + 1]
Raymonds Recovery notreally - IrisSec
Redd’s Art theoldmoon0602 (but we share the one account) - zer0pts
Redd’s Art rpm0618 - SignificantBits
Redd’s Art notreally - IrisSec
Small Oops ptr-yudai - zer0pts
Starter OSINT Quintec - RGBsec
Starter OSINT hulkhogan - Fairy Sector
Starter OSINT matdaneth - [sqrt(-1) + 1]
Starter OSINT skat - IrisSec
Tom Nook Has Stonks notreally - IrisSec
Whats_A_Syscall? ptr-yudai - zer0pts
Whats_A_Syscall? Lone person that played I think. :D - JHDiscord
Whats_A_Syscall? matdaneth - [sqrt(-1) + 1]
Whats_A_Syscall? D4nch3n - HTCPCP://
Whats_A_Syscall? Fane - OpenToAll
Zip Heck Ptomerty - DiceGang
Zip Heck notreally - IrisSec
coelacanth_vault theoldmoon0602 (but we share the one account) - zer0pts
coelacanth_vault HaX0r - Infinity
coelacanth_vault qpwoeirut - RGBsec
coelacanth_vault coconut750750 - Bailey’s Boys
coelacanth_vault skat - IrisSec
cricket32 ptr-yudai - zer0pts
cricket32 signified - KGB_sec
cricket32 FriedGudetama - FriedGudetama (we never bothered submitting flags oops)
cricket32 notreally - IrisSec
deserializeme harrier - Black Bauhinia
deserializeme defund - DiceGang
invalid 123213 - 1123
isabelles_file_encrypt theoldmoon0602 (but we share the one account) - zer0pts
isabelles_file_encrypt signified - KGB_sec
isabelles_file_encrypt qpwoeirut - RGBsec
isabelles_file_encrypt notreally - IrisSec
kernel theKidOfArcrania - takane
login_page I Am (G)root - Isle Be Back
login_page hulkhogan - Fairy Sector
login_page rpm0618 - SignificantBits
nookcrypt Mystiz - Black Bauhinia
nookcrypt adbforlife - PPP
nookcrypt valardragon - DiceGang
nookstop theoldmoon0602 (but we share the one account) - zer0pts
nookstop ranguli - Group 3
nookstop 2.0 FriedGudetama - FriedGudetama
nookstop 2.0 ian - ian
nookstop 2.0 ian - ian
nookstop 2.0 notreally - IrisSec
nookstop 2.0 STeam - STeam
security_question ranguli - Group 3
security_question matdaneth - [sqrt(-1) + 1]
sunken treasure somebodywhostudiesinuk - Black Bauhinia
sunken treasure notreally - IrisSec