When choosing a site-isolated process for a document loaded from a data: URL that was the result of a redirect, Firefox would load that document in the same process as the site that issued the redirect. This bypassed the site-isolation protections against Spectre-like attacks on sites that host an "open redirect". Firefox no longer follows HTTP redirects to data: URLs. This vulnerability affects Firefox < 114.
{
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        {
            "binary_name": "firefox",
            "binary_version": "114.0+build3-0ubuntu0.20.04.1"
        },
        {
            "binary_name": "firefox-dev",
            "binary_version": "114.0+build3-0ubuntu0.20.04.1"
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        {
            "binary_name": "firefox-geckodriver",
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        },
        {
            "binary_name": "firefox-mozsymbols",
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        }
    ],
    "availability": "No subscription required"
}