Not rated
CVE-2020-26958 Firefox did not block execution of scripts with incorrect MIME types when the response was intercepted and cached…
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.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox 83 | earliest → < 83 | 83 |
| Firefox ESR 78.5 | earliest → < 78.5 | 78.5 |
| Thunderbird 78.5 | earliest → < 78.5 | 78.5 |
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