It was discovered that NSS incorrectly handled certain certificates. An attacker could possibly use this issue to cause a denial of service.
{
    "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
    "binaries": [
        {
            "binary_name": "libnss3",
            "binary_version": "2:3.28.4-0ubuntu0.14.04.5+esm3"
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        {
            "binary_name": "libnss3-dev",
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        {
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        {
            "binary_name": "libnss3-tools",
            "binary_version": "2:3.28.4-0ubuntu0.14.04.5+esm3"
        }
    ]
}
          {
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_name": "libnss3",
            "binary_version": "2:3.28.4-0ubuntu0.16.04.9"
        },
        {
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        {
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            "binary_name": "libnss3-tools",
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}