CVE-2020-26958

MediumCVSS 6.1/10Last modified Jun 17, 2026

Description

Firefox did not block execution of scripts with incorrect MIME types when the response was intercepted and cached through a ServiceWorker. This could lead to a cross-site script inclusion vulnerability, or a Content Security Policy bypass. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.

Metrics

CVSS 3.1 6.1/10CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Weakness enumeration

CWE-79

Affected software

No affected versions have been published.

Timeline

Published: Dec 9, 2020
Last modified: Jun 17, 2026
NVD status: Modified

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