PSA: Massive Exploit - PlaceholderAPI (checkitem expansion)

Hey guys, kinda made a post to warn about a possible exploit that could be on your server as well. It's related to a specific PlaceholderAPI expansion called CheckItem. Random new players joined our server, tried a bunch of random commands all sharing the same placeholder. Eventually they made it work doing /ping %checkitem_give_mat:bedrock,amt:2304% This command gave them a full inventory of bedrock, and can be used to spawn in any item in the game. Emergency fix: We fixed it by going into PlaceholderAPI -> config.yml and making "checkitem: give_enabled: false" So if you have the expansion called checkitem, DISABLE IT RIGHT NOW! I don't know more specific details than that, but wanted to post an emergency post regarding it. We are on purpur version git-Purpur-1996, running Minecraft 1.20.1. The ping command is by the CMI plugin, so not sure if it has to be CMI or not.
36 Replies
MrMcyeet
MrMcyeet2y ago
This is old Like really old It's been know for years
Magnus
Magnus2y ago
And it's still enabled by default?
kayohmedy
kayohmedyOP2y ago
Why isn't that shit off by default, seems like a major issue CheckItem needs to fix or get banned of PAPI And there's nothing on google if you search anything related to this
ProGamingDk
ProGamingDk2y ago
or just report it to helpchat ? and get it fixed there
kayohmedy
kayohmedyOP2y ago
Sure, but I wanted it to reach server owners, like you guys
ProGamingDk
ProGamingDk2y ago
well isnt it better to just get it fixed in general?
kayohmedy
kayohmedyOP2y ago
Yes, but the fix might not happen anytime soon So if anyone is vulnerable, fix it now rather than wait for a potential fix
ProGamingDk
ProGamingDk2y ago
have u reported it?
kayohmedy
kayohmedyOP2y ago
GitHub
CheckItem Expansion - Major exploit · Issue #973 · PlaceholderAPI/P...
Confirmation My issue isn't already found on the Issue tracker. My issue is about PlaceholderAPI and not any expansion or external plugin The issue isn't already fixed in a Spigot Release o...
ProGamingDk
ProGamingDk2y ago
isnt ping from a external plugin
Magnus
Magnus2y ago
Yes as he mentioned at the bottom of the post
ProGamingDk
ProGamingDk2y ago
where?
ProGamingDk
ProGamingDk2y ago
'
No description
ProGamingDk
ProGamingDk2y ago
theres nothing about it
Magnus
Magnus2y ago
No description
Magnus
Magnus2y ago
Hm yeah he didn't mention that in the github report
ProGamingDk
ProGamingDk2y ago
which is like a insanely important part to add because it very well could just be bad implementation of the ping command in cmi
MrMcyeet
MrMcyeet2y ago
any command which parses papi placeholders would be able to do it
ProGamingDk
ProGamingDk2y ago
yeah but which commands parses papi placeholders that doesnt require permissions for it that doesnt come from cmi
kayohmedy
kayohmedyOP2y ago
So if I make a malicious papi expansion it’s not PAPIs fault for hosting it and not taking it down? What a joke But I agree no normal commands should be able to run or parse a placeholder Especially if no perms are given
MrMcyeet
MrMcyeet2y ago
Why would it be lmao? Its up to the server owner to either download it or not papi ecloud is just the dist. platform
kayohmedy
kayohmedyOP2y ago
So if I download an expansion that is merely used to parse a placeholder, I’m supposed to expect it to give my players the ability of spawning in items?
ProGamingDk
ProGamingDk2y ago
its not malcious? malicious*
kayohmedy
kayohmedyOP2y ago
I download expansions that is useful for me, I shouldn’t have to worry about default config having major exploits like that
ProGamingDk
ProGamingDk2y ago
all of em do get checked for malware
kayohmedy
kayohmedyOP2y ago
It being enabled by default is malicious imo
MrMcyeet
MrMcyeet2y ago
I agree, its not malicious, just an oversight I think it could be very useful but it shouldnt be parsed in a player-provided input thing i.e. a command Um, it literally is you should be vetting everything you put on your server dont just blindly trust random developers
ProGamingDk
ProGamingDk2y ago
dont think you can specify it in your extension
MrMcyeet
MrMcyeet2y ago
You cant
kayohmedy
kayohmedyOP2y ago
I blindly trusted PAPI but I guess I can’t anymore
MrMcyeet
MrMcyeet2y ago
you shouldnt blindly trust anything tbh
ProGamingDk
ProGamingDk2y ago
well u shouldnt blindly trust anything
MrMcyeet
MrMcyeet2y ago
not in a prod server, anyway
ProGamingDk
ProGamingDk2y ago
lol
kayohmedy
kayohmedyOP2y ago
I kinda have to in many scenarios because source codes are protected and obfuscated, and I am not a programmer anyway so it’s not like I can see if something is bad.
ProGamingDk
ProGamingDk2y ago
only paid plugins are obfuscated/source is hidden (even tho it breaks gpl), if u have a free plugin that is obfuscated/source is hidden, RUN away.

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