CVE-2020-5255

Name	CVE-2020-5255
Description	In Symfony before versions 4.4.7 and 5.0.7, when a `Response` does not contain a `Content-Type` header, affected versions of Symfony can fallback to the format defined in the `Accept` header of the request, leading to a possible mismatch between the response's content and `Content-Type` header. When the response is cached, this can prevent the use of the website by other users. This has been patched in versions 4.4.7 and 5.0.7.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, bugtraq, EDB, Metasploit, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, Mageia, GitHub code/issues, web search, more)
NVD severity	medium
Debian Bugs	961415

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
symfony (PTS)	stretch (security), stretch	2.8.7+dfsg-1.3+deb9u3	fixed
	buster, buster (security)	3.4.22+dfsg-2+deb10u1	fixed
	bullseye, sid	4.4.19+dfsg-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Debian Bugs
symfony	source	jessie	(not affected)
symfony	source	stretch	(not affected)
symfony	source	buster	(not affected)
symfony	source	(unstable)	4.4.8-1	961415

Notes

[buster] - symfony <not-affected> (Introduced in 4.4.0)
[stretch] - symfony <not-affected> (Introduced in 4.4.0)
[jessie] - symfony <not-affected> (Introduced in 4.4.0)
https://symfony.com/blog/cve-2020-5255-prevent-cache-poisoning-via-a-response-content-type-header
https://github.com/symfony/symfony/commit/dca343442e6a954f96a2609e7b4e9c21ed6d74e6