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 `Accept` header of the request, leading to a possible mismatch between the…
Does this matter?
Lower severity and a low EPSS score (1.30%). Track it; it rarely justifies an emergency change on its own.
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 3.1
- 4.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
- EPSS
- 1.30% probability · 69th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-435, CWE-20
- Affected
- sensiolabs/symfony
- Source
- security-advisories@github.com
References
- https://github.com/symfony/symfony/commit/dca343442e6a954f96a2609e7b4e9c21ed6d74e6Patch, Third Party Advisory
- https://github.com/symfony/symfony/security/advisories/GHSA-mcx4-f5f5-4859Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/C36JLPHUPKDFAX6D5WYFC4ALO2K7RDUQ/
- https://symfony.com/blog/cve-2020-5255-prevent-cache-poisoning-via-a-response-content-type-headerThird Party Advisory
- https://github.com/symfony/symfony/commit/dca343442e6a954f96a2609e7b4e9c21ed6d74e6Patch, Third Party Advisory
- https://github.com/symfony/symfony/security/advisories/GHSA-mcx4-f5f5-4859Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/C36JLPHUPKDFAX6D5WYFC4ALO2K7RDUQ/
- https://symfony.com/blog/cve-2020-5255-prevent-cache-poisoning-via-a-response-content-type-headerThird Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.