Symfony 5.3.12 has just been released. Here is a list of the most
important changes:

security #cve-2021-41268 [SecurityBundle] Default signature_properties to the previous behavior (@wouterj)
security #cve-2021-41267 [HttpKernel] Fix missing extra trusted header in sub-request (@jderusse)
security #cve-2021-41270 [Serializer] Use single quote to escape formulas (@jderusse)
bug #44232 [Cache] fix connecting to local Redis sockets (@nicolas-grekas)
bug #44204 [HttpClient] fix closing curl multi handle when destructing client (@nicolas-grekas)
bug #44208 [Process] exclude argv/argc from possible default env vars (@nicolas-grekas)

Want to upgrade to this new release? Because Symfony protects
backwards-compatibility very closely, this should be quite easy. Use
SymfonyInsight upgrade reports
to detect the code you will need to change in your project and
read our upgrade
documentation to learn more.

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version is not maintained anymore? Or only when a security issue is fixed?
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