XML External Entities (XXE) Explained

[@iamwaseem99]

4:12 "S" in XML stands for "Security"....LOL

[@ari_archer]

that's the point hah

[@ShawSumma]

SGML?

[@cyberpro151]

are you a bug bounty hunter?

[@reema6306]

I've spent a week learning XML and XXE, and your video just summarized 80% of what I learned. Great job!

[@TryX10]

Even though most of the time I don't completely understand every bit, I really like your editing and presentation of these (for me) 'complex' topics! Keep it up! You're doing great man!

[@youssefighzane1668]

Well, well, well !! That's more than AMAAAAAAAAAAAZING !!! I was unable to understand XML and XXE as well until I watch your video. Thank you so much !! RECOMMENDED FOR ALL #BUG_BOUNTY_HUNTERS

[@Yaxqb]

The framework for explaining stuff is amazing. About every other video has a ncat -l 1337 command in it, and it has become a standard practice for me in my own work to use that command. The pwnfunction toolbox feels very versatile👍 Really really nice!

[@aniceguy2577]

This is pure gold. Thx for the great content

[@InfiniteLogins]

I really appreciate your video editing techniques. Make the content easy to follow and engaging.

[@dxsp1d3r]

Why didnt i find this before Awesome stuff man Thank you I came to know about this channel from stoks tweets xD

[@thedude8503]

I love this channel, the people in it and the people subscribed to it. Thank you for making it simple

[@zanidd]

I really like the style of your vids! Keep em coming

[@sakyb7]

xxe is just a beginning this line with the background... goosebumps

[@fmattia99]

John's voice is equal to IppSec's voice, this blew my mind :D

[@abdallahdamnat382]

Fel

[@padaloni]

hahahaha not just me that got confused for a second

[@Sercan_Yilmaz]

He is ippsec ;) John Hammond

[@TheZethera]

I just have to say your opening and music are perfect 👌

[@DeltaEchoVictor]

It's name is mortals

[@abdelrhmanali2955]

Your explanation is really AWESOME bro

[@P4cm4n0x]

Best explanation ever. Very very to the point. Thank you :)

[@seewhatseeabc]

Wow love this style. By the way thanks for the super clear explanation. Especially with the examples, super good clear cut examples.

[@domss1174]

Loving your channel man, keep up the good work!

[@petervsjim]

THanks for the awesome video and slides! Very clear and knowledgeable

[@FriedMonkey362]

I have litterly never heard about this before, this is so cool, i almost tought it was an April fool's video for a second

[@overgrowncarrot1]

I like how John hammond says I have a small youtube channel lol

[@joshaprior3699]

first GREAT CHANNEL

[@tapank415]

@// Anuj ó_ó

[@rhenaldodelfinugraha9694]

Awesome explanation. It's easy to understand, Thankyou. Please make another cool videos

[@venkaraj]

Such an insightful video. Thanks a ton

[@HyderAli-hl8mw]

Very informational for beginners. Thank you so much

[@iDontProgramInCpp]

3:56 diReRectly

[@synthdog2819]

17:06 willbewillbe

[@rahulnair1923]

Loved the explanation !!!!!!!!!!🤩

[@SatsJava]

You deserved million subscriber Keep make more videos mate

[@PwnFunction]

Well that's a longgggggggggg way. Don't think I could ever hit such crazy numbers, If I hit 10k then I feel like I've accomplished something :) but thanks.

[@0xExploitXpErtz]

@@PwnFunction u will surely achieve it IA

[@mikekittelberger7947]

omg, thank you. This video is so godd :)

[@Hope-kf1nl]

You're a hero! Thanks my man.

[@neadlead2621]

thanks bro , I've one question at 18:05 why we need %start and %end why not changing them directely to the value

[@pwndumb2903]

Great Video. Thx for share your knowledge.

[@patricksteinmuller8084]

Tbh. I wonder why anyone would use DTD anyhow? The reason I am so fond of XML is the existence of XSD and XSLTs. A well defined XML is both human readible and machine readible. Can be validated against an XSD, can be transformed against an XSLT and have XSD, XSLT and both XML input and XML ouput validated against respective XSDs. This is not something that we have for json or yaml. I was to lazy to look ... I somehow suspect that we have similar attack vectors in the X* Suite.

[@medjassertoubib4467]

great video . we look forward to new videos

[@giospadaccini119]

In Italy xml is use to send invoices to the IRS, and after few day it sand that to you client .... So this video reassuring me..

[@anonymouseye4892]

Nice explanation 🔥

[@devsingh6041]

this video is sufficient to understand XXE. Thanks Pwn You Func well ;-)

[@kinjalsangale1225]

Please make more videos on different vulnerabilities... explainions are 👌

[@faizannehal1]

This is the best video on XXE

[@janithmalinga5765]

Superb explanation

[@coastaldemigod]

my engineering professor taught the first 10 mins. of this video in 1 month

[@stefaunholland6642]

The way you say "parameter" makes me think of a parking meter with a parachute falling out the sky - an American

[@emmanuelafolabi6847]

Great videom your videos has been educative, can you make a video on based XSS?

[@PwnFunction]

Next one!

[@nuridincersaygili]

This is pure gold..

[@shrirangdiwakar]

Great Explanation !

[@BALAKRISHNAN-pf1ol]

Can you attatch a link to the xml parser you used in the video

[@AkashRaj-ui1pj]

Your videos are a aaaaaaaaaamaaaaaazinggggg

[@carloszavaleta]

Awesome content!

[@zxuiji]

2:42, already think of JSON as easier, just use a string and escape the quote characters **Edit:** I also prefer lua when I need more than just data capabilities

[@hydr0nium_]

Never heared of that attack before the video. Soo wow amazing. If you think about it its quite simple actually. Btw is there a way of secure it easiely?

[@aleksandar5323]

How can I disable XML parser resources referencing on say an Apache Server? I don't want XML to be making any requests at all, either internal or God forbid accessing a 3rd party URL! I just want hard-coded data from it...

[@helloguy1179]

What should I do if I have to configure a http request to get a file's information, but its content contains special character? We cannot use CDATA in a URL, right?

[@eshaan7_]

What theme for VScode and terminal are u using? BTW Great video, thanks!

[@PwnFunction]

Monokai Pro Terminus - eugeny.github.io/terminus/

[@Manabender]

So how does one defend against this? Say I was running the server you were attacking and *didn't* want you reading /etc/passwd, but still wanted to retain as much (safe) functionality of the XML parser as possible. What would I do?

[@annomy1493]

voice seems to be known. Is it john harmmond ???

[@vijaykumar-hc6jz]

Why DTD is so called ? It could have also been called Entity Defintition or something like that ? Any answer to this is appeciated.

[@ashleypursell9702]

great video thanks so much

[@uplink-on-yt]

My reaction (comment, not video): eyes open wide, mouth covered with hand, deep breath - AKA "Surprised Pikachu". This is possibly one ofvthe most evil things I've ever seen (yeah... I'm pretty innocent)

[@vxjmrf]

& sign showing error while referencing an entity. I tried in ascii or hex too, it is not working. Is there any other ways to reference it?

[@huntit4578]

What software do u use to make these slideshow or animation (Whatever) to explain these attacks in such a interesting way?

[@tanishqsachdev8388]

Amazing video.

[@aymanrbati531]

why cant u declare the "send" entity directly in the external DTD ? why put it inside 'wrapper' ?

[@prudhvidanyamraju8017]

On a certain java server I’m able to retrieve the data of /sys/power/image_size (basically an number) using OOB xxe but I’m unable to retrieve contents of etc/passwd ; any thoughts?

[@patrickslomian7423]

Love your channel Bro !! So I ran into a failure with Dvwa in the section "file upload",I"ve tried to upload an file with the payload. It seems to me that the server (using docker) wont phrase an xml file, can that be true ? Im getting this error :" This XML file does not appear to have any style information associated with it. The document tree is shown below. " Or should I converte that to an html file ?

[@Sparkette]

Is it okay to use a '

[@laurinneff4304]

It would've been great if you had included a segment on how to protect against these attacks

[@Morgan_iv]

Just don't use XML

[@xf4229]

I am having issue accessing id_rsa in .ssh file. Is there any way to bypass it? The current issue is I/O warning: fail to load external entity.

[@Wikkido5000]

do you have a similar video for JSON?

[@Pcpiee]

What terminal do you use for the examples? it looks very nice. guessing its cygwin based by the looks of it

[@PwnFunction]

Terminus - eugeny.github.io/terminus/

[@G0NZA11]

I get lost at 15:17. Who is responsible for doing the replacements? If it is attacker.com's server it should have the passwords of attacker in $CONTENTS_OF_PASSWD, and if s/he serves it as raw then the other (pwn.com?) should be responsible for the replacement, then it shouldn't work because you can't have a '%' inside an entity, just as before.

[@PwnFunction]

The replacements that I've show in the video is just so people can understand it a bit better. During the time of xml parsing on a vulnerable application, entities are replaced like I've talked about. The code @ 15:17 is not accurate, it's more like a parsed representation, so you might wanna see the demo bit 15:38 to understand it a bit more with the real code.

[@CosmoCopulates1]

Dude, your videos are great! What do you use to create the animations?

[@PwnFunction]

Adobe animate boi.

[@SatriaAdyPradana]

do you have git repo which collect the scripts and XML files used here?

[@AakanshYadav-b6t]

hey hey hey sir please tell this theme of zsh. I tried searching all of them but i didn't find anyone like this please do tell.

[@tuttifrutti4184]

holy shit this is so hard to understand, but I suppose it's supposed to be this way unless you actually practise using XML for quite some time

[@muhammadadel9537]

Super AWESOME!!

[@heycherry100]

very nice video.

[@aidenrhama9147]

what software did you use to make this content ?

[@generalinformation3194]

hello can i get the xmlsax_parser tool you use it in the video plz

[@jasonmikinskiwallet4308]

I love the Intro

[@eduardoandrescastilloperer4810]

OMG why was that even encoded into the standard!!!

[@puravida012]

this is soo old, HTB show something like this almost a year ago

[@PwnFunction]

Yeah it's very old, you can even find stuff about it, way back in 2002. www.securityfocus.com/archive/1/297714/2002-10-27/2002-11-02/0

[@alexeecs]

So... How do you defend against it?

[@asjidkalam]

is stok's video on OOB XXE private?

[@d86123]

那麼...問題是，如何防止XXE注入攻擊呢?

[@JD-mz1rl]

I don't get it. Unless the web server is running with root permissions, what useful files are you going to get out of it?

[@Aidiakapi]

It's not just for web servers, it can compromise clients too. Getting someone to open a document and extract information. As for what useful files, plenty of web servers will have access to many useful files. Configuration files, uploaded artifacts, etc.

[@ctfs09]

there is something you need to explore more! You don't have to be root, its not about editing , it is just exfiltrating and you don't have to be root! Try cat /etc/passwd without being root and even you can see that.

[@lexibigcheese]

so that's why there's a doctype html. that's what it's for!

[@r4nd0m25]

god level videos

[@mylyf6684]

Hai bro will you please share that python script for parsing XML. please...

[@PwnFunction]

I don't have the code, but it was a simple sax xml parser written in python - docs.python.org/3/library/xml.sax.reader.html

[@kallikantzaros]

from lxml import etree parser = etree.XMLParser(load_dtd=True, no_network=False) tree = etree.parse("main_attack.xml", parser=parser) etree.dump(tree.getroot())

[@itizazadil9369]

Thanks for the Vedio

[@hellb0y794]

your sound like @liveoverflow, are you his brother? 😆

[@learnfirst-1]

I hate background color 🤦‍♂️🤦‍♂️🤦‍♂️🤦‍♂️ change to white color pls But contant is AAmazinggggg👍👍

[@jagc2206]

Xml is so stupid, but maybe it's just that everything using xml is old and "legacy" and thus has a bad structure (or just one for internal us only) and it thus extremely frustrating. I am currently working on a 50k line xml, I don't use the dtds or any other of the extanal information in the document, but I clicked on some links and most of them are 404s at this point................ But hey its better than csv with sometimes quotes, sometimes not containing ~ seperated arrays, with inconsequent formating and id values

[@WhyetCecilia-v8u]

Bartoletti Landing

[@yeasirarafat4261]

awesome

[@u0000-u2x]

can you link that python xml parser?

[@PwnFunction]

I don't have the code with me, but I hope this can be helpful - docs.python.org/3/library/xml.sax.reader.html

[@acunsumageka3949]

tools for xml parser ?

[@ArthurBurke-c5n]

Heidenreich Walks

[@zanidd]

I'd like to do a similar style collab, if you're into it send me an email!

[@GeordieJuliet]

1980 Noble Walk

[@IBMboy]

9:47 My name is jeff. Nice meme

[@anatolyrapoport2216]

Nice tutorial!