Contributed by Jérémy Derussé in #39919.
BREACH is a security exploit against HTTPS when using HTTP compression. This kind of compression side-channel attacks are used to read some data by knowing only the size of the compressed data. Your site is at risk if attackers can read the size of your encrypted traffic and can also make any number of HTTP requests with CSRF tokens. The traditional way of mitigating this attack was to disable HTTP compression, which hurts performance significantly. Another possible solution is to ensure that CSRF tokens include some randomness, to prevent repetitive output in your responses. That’s why in Symfony 5.3 CSRF tokens are automatically randomized. This randomization process is transparent to the application, so you don’t need to configure anything and you don’t need to change your application code. If you disabled compression when using HTTPS because of this attack, upgrade to Symfony 5.3 and enable compression again to improve your site performance. This is yet another reason why using a professional framework like Symfony is better in the long run. Symfony will protect your application and your users against many common security vulnerabilities, even those you are not aware of.
Sponsor the Symfony project.Login to add comment
Other posts in this group
Thank you for joining us at SymfonyOnline June 2025!
What a great edition of SymfonyOnline we’ve just wrapped up! 🎉
We were thrilled to welcome 300 participants from 35 different countries—a
This week, Symfony celebrated the SymfonyOnline June 2025 conference with great success. Meanwhile, development efforts focused on improving invokable commands for the upcoming Symfony 7.4 version. Th
This week, development activity focused on the upcoming Symfony 7.4 and 8.0 versions, which will deprecate and remove many features. In addition, we published a case study about Yousign. Finally, we'r
As digital signatures become the norm in modern business, Yousign has established itself as a trusted leader across Europe. Behind its simple, intuitive interface is a powerful technical engine, handl
Get ready for the exciting SymfonyOnline June 2025, kicking off in a few days only! There’s still time to register and join the international online Symfony conference—along with pre-conferenc
This week, Symfony released the stable version of Symfony 7.3, which includes lots of amazing new features. We also published the maintenance versions 6.4.22 and 7.2.7.
Symfony development highlights
This is the second part of the blog post showcasing the main DX (developer experience) features introduced in Symfony 7.3. Read the first part of this blog post.
Verify URI Signatures… https://symfon
