[USN-3850-2] NSS vulnerabilities

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Ubuntu Security Notice USN-3850-2
February 18, 2019

nss vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 12.04 ESM

Summary:

Several security issues were fixed in NSS.

Software Description:
- nss: Network Security Service library

Details:

USN-3850-1 fixed several vulnerabilities in NSS. This update provides
the corresponding update for Ubuntu 12.04 ESM.

Original advisory details:

 Keegan Ryan discovered that NSS incorrectly handled ECDSA key
 generation. A local attacker could possibly use this issue to perform
 a cache-timing attack and recover private ECDSA keys. (CVE-2018-0495)

 It was discovered that NSS incorrectly handled certain v2-compatible
 ClientHello messages. A remote attacker could possibly use this issue
 to perform a replay attack. (CVE-2018-12384)

 It was discovered that NSS incorrectly handled certain padding
 oracles. A remote attacker could possibly use this issue to perform a
 variant of the Bleichenbacher attack. (CVE-2018-12404)

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 12.04 ESM:
  libnss3                         2:3.28.4-0ubuntu0.12.04.2

After a standard system update you need to restart any applications
that use NSS, such as Evolution, to make all the necessary changes.

References:
  https://usn.ubuntu.com/usn/usn-3850-2
  https://usn.ubuntu.com/usn/usn-3850-1
  CVE-2018-0495, CVE-2018-12384, CVE-2018-12404