this post was submitted on 10 Aug 2023
556 points (97.9% liked)
Programmer Humor
19512 readers
366 users here now
Welcome to Programmer Humor!
This is a place where you can post jokes, memes, humor, etc. related to programming!
For sharing awful code theres also Programming Horror.
Rules
- Keep content in english
- No advertisements
- Posts must be related to programming or programmer topics
founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
The problem is that when you compress before you encrypt, the file size becomes a source of data about the contents. If an attacker has control of part of the data - say - a query string, they can use that to repeatedly add things to your data and see how the size changes as a result.
So it sounds like compression before encryption should only be done in specific circumstances because it can be a security issue depending on use case, but encryption before compression should never be done because it will almost always increase the size of the file