When String.toUpperCase() caused a string to get longer it was possible for uninitialized memory to be incorporated into the result string This vulnerability affects Firefox < 136 and Thunderbird < 136.
{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_name": "firefox",
            "binary_version": "136.0+build3-0ubuntu0.20.04.1"
        },
        {
            "binary_name": "firefox-dev",
            "binary_version": "136.0+build3-0ubuntu0.20.04.1"
        },
        {
            "binary_name": "firefox-geckodriver",
            "binary_version": "136.0+build3-0ubuntu0.20.04.1"
        },
        {
            "binary_name": "firefox-mozsymbols",
            "binary_version": "136.0+build3-0ubuntu0.20.04.1"
        }
    ]
}