If you're parsing XML then external entities (allowing local file inclusion or server side request forgery) are much more dangerous for you than this denial of service. OWASP has a cheat sheet for disabling XXE on a few different parsers:
EDIT: In spite of those who are downvoting my comment without even replying, I'm leaving it anyway; cause sharing good software outweighs whatever loss they intend to inflict.
I think that Rust has captured many developers that previously used Javascript, so it's their first introduction to things like static typing. As a result they are amazed that a compiler can show them errors in their code before it's run.
Interestingly, many browsers are still susceptible to this attack, for example when used in SVG files (WARNING: might crash your browser and/or operating system): https://jsfiddle.net/e3guLn08/
Browsers are susceptible to a server that generates an infinite HTML page (e.g. CGI shell script calling "yes <arg>"), and also to thing called JavaScript that can eat all your memory programmatically (and does exactly so on a regular basis).
This was been around for well over a decade. Interestingly though, denial of service is the less interesting issue that external entity parsing comes with. It can lead all the way to data exfiltration and remote code execution.
This is loads of fun against batteries included web frameworks like rail, grails, play framework and so on. Not sure about now, but a few years ago basically all of them were susceptible to this and XXE and it was extremely difficult to disable in the XML parsers.
> A "Billion laughs" attack should exist for any file format that can contain references, for example this YAML bomb:
C preprocessor?
$ gcc -E - | wc
#define EXP(X) X X X X X X X X X X X X X X X X
#define LOL1 EXP(LOL)
#define LOL2 EXP(LOL1)
#define LOL3 EXP(LOL2)
#define LOL4 EXP(LOL3)
#define LOL5 EXP(LOL4)
LOL5
[Ctrl-D][Enter]
11 1048588 4194376
Not normally considered a "file format", though. People don't open a C preprocessor attachment in their e-mail only to have some application grind their PC and crash. Or use this for RPC calls and whatnot.
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[ 4.3 ms ] story [ 58.9 ms ] threadhttps://www.owasp.org/index.php/XML_External_Entity_(XXE)_Pr...
0: https://en.m.wikipedia.org/wiki/Zip_bomb
https://github.com/Keats/scl
EDIT: In spite of those who are downvoting my comment without even replying, I'm leaving it anyway; cause sharing good software outweighs whatever loss they intend to inflict.
"Btw I use Rust".
I don't get your analogy.
How do you know someone uses "X"? Don't worry, they'll tell you.
The desk sergeant asks, "Can you describe the mugger?"
"Not really, he grabbed me from behind. I know he's a man, bigger than me, and he's vegan."
"How on earth do you know he's vegan?"
"He bloody told me!"
C preprocessor?
Not normally considered a "file format", though. People don't open a C preprocessor attachment in their e-mail only to have some application grind their PC and crash. Or use this for RPC calls and whatnot.