A new release of the Ubuntu Cloud Images for stable Ubuntu release 20.10 (Groovy Gorilla) 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 These new images superseded the existing images [2].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:
 * git: 1:2.27.0-1ubuntu1 => 1:2.27.0-1ubuntu1.1 
 * glib2.0: 2.66.1-2 => 2.66.1-2ubuntu0.1 
 * libzstd: 1.4.5+dfsg-4 => 1.4.5+dfsg-4ubuntu0.1 
 * linux-meta: 5.8.0.44.49 => 5.8.0.45.50 
 * linux-signed: 5.8.0-44.50 => 5.8.0-45.51 
 * openssh: 1:8.3p1-1 => 1:8.3p1-1ubuntu0.1 
 * update-manager: 1:20.10.4 => 1:20.10.5 


The following is a complete changelog for this image.
new: {'linux-headers-5.8.0-45': '5.8.0-45.51', 'linux-modules-5.8.0-45-generic': '5.8.0-45.51', 'linux-headers-5.8.0-45-generic': '5.8.0-45.51'}
removed: {'linux-headers-5.8.0-44-generic': '5.8.0-44.50', 'linux-headers-5.8.0-44': '5.8.0-44.50', 'linux-modules-5.8.0-44-generic': '5.8.0-44.50'}
changed: ['git', 'git-man', 'libglib2.0-0:amd64', 'libglib2.0-bin', 'libglib2.0-data', 'libzstd1:amd64', 'linux-headers-generic', 'linux-headers-virtual', 'linux-image-5.8.0-45-generic', 'linux-image-virtual', 'linux-virtual', 'openssh-client', 'openssh-server', 'openssh-sftp-server', 'python3-update-manager', 'update-manager-core']
new snaps: {}
removed snaps: {}
changed snaps: ['lxd', 'snapd']
==== git: 1:2.27.0-1ubuntu1 => 1:2.27.0-1ubuntu1.1 ====
====     git git-man
  * SECURITY UPDATE: remote code exec during clone on case-insensitive FS
    - debian/patches/CVE-2021-21300.patch: fix bug that makes checkout
      follow symlinks in leading path in cache.h, compat/mingw.c,
      git-compat-util.h, run-command.c, symlinks.c, t/t0021-conversion.sh,
      t/t0021/rot13-filter.pl, t/t2006-checkout-index-basic.sh,
      unpack-trees.c.
    - CVE-2021-21300
==== glib2.0: 2.66.1-2 => 2.66.1-2ubuntu0.1 ====
====     libglib2.0-0:amd64 libglib2.0-bin libglib2.0-data
  * SECURITY UPDATE: g_byte_array_new_take length truncation
    - debian/patches/CVE-2021-2721x/CVE-2021-27218.patch: do not accept too
      large byte arrays in glib/garray.c, glib/gbytes.c,
      glib/tests/bytes.c.
    - CVE-2021-27218
  * SECURITY UPDATE: integer overflow in g_bytes_new
    - debian/patches/CVE-2021-2721x/CVE-2021-27219*.patch: add internal
      g_memdup2() function and use it instead of g_memdup() in a bunch of
      places.
    - CVE-2021-27219
==== libzstd: 1.4.5+dfsg-4 => 1.4.5+dfsg-4ubuntu0.1 ====
====     libzstd1:amd64
  * SECURITY UPDATE: race condition allows attacker to access
    world-readable destination file
    - debian/patches/0018-fix-file-permissions-on-compression.patch: set
      umask in programs/fileio.c, programs/util.c, programs/util.h.
    - CVE-2021-24031
    - CVE-2021-24032
==== linux-meta: 5.8.0.44.49 => 5.8.0.45.50 ====
====     linux-headers-generic linux-headers-virtual linux-image-virtual linux-virtual
  * Bump ABI 5.8.0-45
==== linux-signed: 5.8.0-44.50 => 5.8.0-45.51 ====
====     linux-image-5.8.0-45-generic
  * Master version: 5.8.0-45.51
==== openssh: 1:8.3p1-1 => 1:8.3p1-1ubuntu0.1 ====
====     openssh-client openssh-server openssh-sftp-server
  * SECURITY UPDATE: double-free memory corruption in ssh-agent
    - debian/patches/CVE-2021-28041.patch: set ext_name to NULL after
      freeing it so it doesn't get freed again later on in ssh-agent.c.
    - CVE-2021-28041
==== update-manager: 1:20.10.4 => 1:20.10.5 ====
====     python3-update-manager update-manager-core
  * UpdateManager/Core/UpdateList.py: change to a regex from a static list
    of packages to be grouped under Ubuntu Base (LP: #1902025)
  * Clean up apt cache binary files left behind by tests
  * Rename meta_pkgs to ubuntu_base_pkgs to make it more clear to the
    reader which packages should be included
  * Add tests in to ensure Ubuntu base packages are not grouped when
    staged for removal (LP: #1912718)
  * Fix crash caused by adding apt package objects to a list of
    strings (LP: #1913476)

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[1] http://cloud-images.ubuntu.com/releases/groovy/release-20210315/
[2] http://cloud-images.ubuntu.com/releases/groovy/release-20210303/