Karthikeyan Bhargavan discovered that NSS incorrectly handled state transitions for the TLS state machine. If a remote attacker were able to perform a machine-in-the-middle attack, this flaw could be exploited to skip the ServerKeyExchange message and remove the forward-secrecy property. (CVE-2015-2721)
Watson Ladd discovered that NSS incorrectly handled Elliptical Curve Cryptography (ECC) multiplication. A remote attacker could possibly use this issue to spoof ECDSA signatures. (CVE-2015-2730)
As a security improvement, this update modifies NSS behaviour to reject DH key sizes below 768 bits, preventing a possible downgrade attack.
This update also refreshes the NSS package to version 3.19.2 which includes the latest CA certificate bundle.
{
"availability": "No subscription required",
"binaries": [
{
"binary_version": "2:3.19.2-0ubuntu0.14.04.1",
"binary_name": "libnss3"
},
{
"binary_version": "2:3.19.2-0ubuntu0.14.04.1",
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{
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{
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{
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]
}
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-2672-1.json"
{
"cves": [
{
"id": "CVE-2015-2721",
"severity": [
{
"type": "Ubuntu",
"score": "medium"
}
]
},
{
"id": "CVE-2015-2730",
"severity": [
{
"type": "Ubuntu",
"score": "medium"
}
]
}
],
"ecosystem": "Ubuntu:14.04:LTS"
}