I think the claim is hyperbolic, since most people memory-unsafe PDF implementations, but PDF is a monster format, a metaformat that brings in virtually every conceivable display format, and their renderer implementations with them, often poorly-maintained, never-touched reference implementations from the before times. PDF is pretty scary.
PDFs are usually untrusted input and C provides no assurance there isn't a bug in the code that allows corrupted input to turn into arbitrary remote code execution.
File formats are the buffer issue honeypot. You may be aware of how often video and audio codecs have vulnerabilities - it's nearly never the hand-tuned frame decode assembly (where you would think all the mistakes would be). It's nearly always the thing that reads the metadata and encoded frames to memory. Binary formats have things like offsets in them, and those can be trivially used to overrun.
Same thing applies here. Even Rust has a crate for dealing with binary data, despite its memory promises: https://crates.io/crates/untrusted
It's a fucking minefield, and this is one area where the Rust zealots are undeniably correct. It doesn't have to be Rust, any memory safe language will do, but Rust also happens to be performance competitive and that's usually also desirable.
The technology you want for this sort of work is WUFFS, for Wrangling Untrusted File Formats Safely.
Rust is a general purpose programming language, which is great if your problem might be something never imagined before, but this literally isn't our first rodeo, we have wrangled lots of file formats before, we should use a language purpose-built to do that safely.
btw, the idea that the system rng isnt good enough, or "runs out" or whatever, is no longer true on pretty much every modern, widely used os.
btw... im sure there's some legacy rng in windows or some shit that isnt good. read the docs but if it's the blessed system rng, you're probably fine!
although... i suppose if this is news to you (the person reading this), then you probably shouldn't be implementing whatever you are that really requires prng. ask a friend for help. im not trying to be a jerk, i just want to make sure you dont hurt yourself!
good point about VMs. if you run some VPS your provider could just link in a shitty rng into the thing and not give access to the correct hardware rng. U'd really need to dig into that to find out :/.
"MuPDF versions before 1.28.5 use an implementation of the drand48 family" yeah, ok, so they're basically not doing real encryption. The number of bits in the key space isn't the real story; the keys simply aren't cryptographically random.
What is wrong with software engineers that we keep making really stupid basic mistakes like this? Sometimes I think programming should require licensing and regular testing.
University degrees are not the difference between an engineer and a developer, universities have churned out millions of people who don't care about programming and have no idea what they're doing, who are just following the script with as little effort as possible because they were told it was the easiest way to make a lot of money.
We direly need to split things into a licensed engineering field which is necessary for working on security- and reliability-critical systems, and a generic unlicensed software developer field where people can screw around with their 1000 dependency JS frontends to their hearts' content. The two should not be conflated and yet so easily are.
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[ 0.15 ms ] story [ 64.6 ms ] threadSame thing applies here. Even Rust has a crate for dealing with binary data, despite its memory promises: https://crates.io/crates/untrusted
It's a fucking minefield, and this is one area where the Rust zealots are undeniably correct. It doesn't have to be Rust, any memory safe language will do, but Rust also happens to be performance competitive and that's usually also desirable.
Rust is a general purpose programming language, which is great if your problem might be something never imagined before, but this literally isn't our first rodeo, we have wrangled lots of file formats before, we should use a language purpose-built to do that safely.
I don't understand how I hit the anti-Rust tripwire here:
> My comment: any memory safe language will do
You can downvote anything not interesting.
If he have list some alternative or give example, it might be interesting.
Rule #2? Please don’t.
btw... im sure there's some legacy rng in windows or some shit that isnt good. read the docs but if it's the blessed system rng, you're probably fine!
although... i suppose if this is news to you (the person reading this), then you probably shouldn't be implementing whatever you are that really requires prng. ask a friend for help. im not trying to be a jerk, i just want to make sure you dont hurt yourself!
And if you're a sysadmin, be extremely careful when generating keys in VMs or embedded devices.
-object rng-random,id=objrng0,filename=/dev/null
or maybe just a file that contains 4 :O
Rule 3b: Failing rule 3, disclose motivations and full list of employers and / or customers
The human bar is not that high.
I would much rather have rigorous testing than a filter based on the origin of the code.
Would the new LLM model owners like to strike this down, or use it to demonstrate how dangerous unrestricted models can be?