Severity

Low

Vendor

Canonical Ubuntu

Versions Affected

• Canonical Ubuntu 14.04
• Canonical Ubuntu 16.04
• Canonical Ubuntu 18.04

Description

Samuel Weiser discovered that OpenSSL incorrectly handled DSA signing. An attacker could possibly use this issue to perform a timing side-channel attack and recover private DSA keys. (CVE-2018-0734)

Samuel Weiser discovered that OpenSSL incorrectly handled ECDSA signing. An attacker could possibly use this issue to perform a timing side-channel attack and recover private ECDSA keys. This issue only affected Ubuntu 18.04 LTS and Ubuntu 18.10. (CVE-2018-0735)

Billy Bob Brumley, Cesar Pereida Garcia, Sohaib ul Hassan, Nicola Tuveri, and Alejandro Cabrera Aldaya discovered that Simultaneous Multithreading (SMT) architectures are vulnerable to side-channel leakage. This issue is known as “PortSmash”. An attacker could possibly use this issue to perform a timing side-channel attack and recover private keys. (CVE-2018-5407)

CVEs contained in this USN include: CVE-2018-0734, CVE-2018-0735, CVE-2018-5407

Affected Cloud Foundry Products and Versions

Severity is low unless otherwise noted.

• Cloud Foundry BOSH trusty-stemcells are vulnerable, including:
  • 3586.x versions prior to 3586.65
  • 3541.x versions prior to 3541.69
  • 3468.x versions prior to 3468.90
  • 3445.x versions prior to 3445.87
  • 3421.x versions prior to 3421.104
  • All other stemcells not listed.
• Cloud Foundry BOSH xenial-stemcells are vulnerable, including:
  • 170.x versions prior to 170.14
  • 97.x versions prior to 97.41
  • All other stemcells not listed.
• All versions of Cloud Foundry cflinuxfs2 prior to 1.254.0
• All versions of Cloud Foundry cflinuxfs3 prior to 0.46.0

Mitigation

Users of affected products are strongly encouraged to follow one of the mitigations below:

• The Cloud Foundry project recommends upgrading the following BOSH trusty-stemcells:
  • Upgrade 3586.x versions to 3586.65
  • Upgrade 3541.x versions to 3541.69
  • Upgrade 3468.x versions to 3468.90
  • Upgrade 3445.x versions to 3445.87
  • Upgrade 3421.x versions to 3421.104
  • All other stemcells should be upgraded to the latest version available on bosh.io.
• The Cloud Foundry project recommends upgrading the following BOSH xenial-stemcells:
  • Upgrade 170.x versions to 170.14
  • Upgrade 97.x versions to 97.41
  • All other stemcells should be upgraded to the latest version available on bosh.io.
• The Cloud Foundry project recommends that Cloud Foundry deployments run with cflinuxfs2 version 1.254.0 or later.
• The Cloud Foundry project recommends that Cloud Foundry deployments run with cflinuxfs3 version 0.46.0 or later.

References

• USN-3840-1
• CVE-2018-0734
• CVE-2018-0735
• CVE-2018-5407