A new release of the Ubuntu Cloud Images for stable Ubuntu release 18.04 LTS (Bionic Beaver) is available at [1]. These new images superseded the existing images [2]. Images are available for download or immediate use on EC2 via publish AMI ids. Users who wish to update their existing installations can do so with:
   'sudo apt-get update && sudo apt-get dist-upgrade && sudo reboot'.

The following packages have been updated. Please see the full changelogs
for a complete listing of changes:
 * linux-meta: 4.15.0.153.142 => 4.15.0.154.143 
 * linux-signed: 4.15.0-153.160 => 4.15.0-154.161 
 * openssh: 1:7.6p1-4ubuntu0.3 => 1:7.6p1-4ubuntu0.5 
 * openssl: 1.1.1-1ubuntu2.1~18.04.9 => 1.1.1-1ubuntu2.1~18.04.10 
 * systemd: 237-3ubuntu10.50 => 237-3ubuntu10.51 


The following is a complete changelog for this image.
new: {'linux-headers-4.15.0-154': '4.15.0-154.161', 'linux-modules-4.15.0-154-generic': '4.15.0-154.161', 'linux-headers-4.15.0-154-generic': '4.15.0-154.161'}
removed: {'linux-headers-4.15.0-153-generic': '4.15.0-153.160', 'linux-modules-4.15.0-153-generic': '4.15.0-153.160', 'linux-headers-4.15.0-153': '4.15.0-153.160'}
changed: ['libnss-systemd:amd64', 'libpam-systemd:amd64', 'libssl1.1:amd64', 'libsystemd0:amd64', 'libudev1:amd64', 'linux-headers-generic', 'linux-headers-virtual', 'linux-image-4.15.0-154-generic', 'linux-image-virtual', 'linux-virtual', 'openssh-client', 'openssh-server', 'openssh-sftp-server', 'openssl', 'systemd', 'systemd-sysv', 'udev']
new snaps: {}
removed snaps: {}
changed snaps: []
==== linux-meta: 4.15.0.153.142 => 4.15.0.154.143 ====
====     linux-headers-generic linux-headers-virtual linux-image-virtual linux-virtual
  * Bump ABI 4.15.0-154
  * Packaging resync (LP: #1786013)
    - [Packaging] resync debian/dkms-versions from main package
==== linux-signed: 4.15.0-153.160 => 4.15.0-154.161 ====
====     linux-image-4.15.0-154-generic
  * Master version: 4.15.0-154.161
==== openssh: 1:7.6p1-4ubuntu0.3 => 1:7.6p1-4ubuntu0.5 ====
====     openssh-client openssh-server openssh-sftp-server
  * SECURITY REGRESSION: User enumeration issue (LP: #1934501)
    - debian/patches/CVE-2018-15473.patch: updated to fix bad patch
      backport.
  * Apply upstream patch to stop using 2020 as a future date in regress
    tests. LP: #1859013
==== openssl: 1.1.1-1ubuntu2.1~18.04.9 => 1.1.1-1ubuntu2.1~18.04.10 ====
====     libssl1.1:amd64 openssl
  * Cherry-pick an upstream patch to fix s390x AES code (LP: #1931994)
==== systemd: 237-3ubuntu10.50 => 237-3ubuntu10.51 ====
====     libnss-systemd:amd64 libpam-systemd:amd64 libsystemd0:amd64 libudev1:amd64 systemd systemd-sysv udev
  * Add support to keepconfiguration (LP: #1815101)
    - lp1815101-0001-add-macro-if-flags-are-set.patch
    - lp1815101-0002-networkd-add-support-to-keepconfiguration.patch
    - lp1815101-0003-network-use-hashmap_steal_first-rather-than-hashmap_.patch
    - lp1815101-0004-networkd-stop-clients-when-networkd-shuts-down.patch
    - lp1815101-0005-network-add-KeepConfiguration-dhcp-on-stop.patch
    - lp1815101-0006-network-make-KeepConfiguration-static-drop-DHCP-addr.patch
    - lp1815101-0007-man-add-documentation-about-KeepConfiguration.patch

--
[1] http://cloud-images.ubuntu.com/releases/bionic/release-20210817/
[2] http://cloud-images.ubuntu.com/releases/bionic/release-20210804/