CVE-2020-5255
Estado: ModificadaMedia (4.3)—
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
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
- Puntuación base: 4.3
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.30%
- Percentil entre todas las CVEs puntuadas: 69
- Fecha de la puntuación: 7/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
CWE
- CWE-435
- CWE-20
Referencias
- https://github.com/symfony/symfony/commit/dca343442e6a954f96a2609e7b4e9c21ed6d74e6
- https://github.com/symfony/symfony/security/advisories/GHSA-mcx4-f5f5-4859
- 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-header
- https://github.com/symfony/symfony/commit/dca343442e6a954f96a2609e7b4e9c21ed6d74e6
- https://github.com/symfony/symfony/security/advisories/GHSA-mcx4-f5f5-4859
- 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-header
JSON original (NVD)
Mostrar
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