Medium severity · published Mar 30, 2020
CVE-2020-5255
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…
4.3
CVSS
1.3%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.3% · higher than 70% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SY
Symfony · Sensiolabs
4.4.0 before 4.4.7; 5.0.0 before 5.0.7 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-5255
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-5255
Patch
https://github.com/symfony/symfony/commit/dca343442e6a954f96a2609e7b4e9c21ed6d74e6
Third Party Advisory
https://github.com/symfony/symfony/security/advisories/GHSA-mcx4-f5f5-4859
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/C36JLPHUPKDFAX6D5WYFC4ALO2K7RDUQ/
Third Party Advisory
https://symfony.com/blog/cve-2020-5255-prevent-cache-poisoning-via-a-response-content-type-header
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