Hi,

PackageKit allows to downgrade packages. For example tiff here has a
security update that the logged in user can undo:

$ pkcon get-updates
Getting updates               [=========================]
Waiting in queue              [=========================]
Starting                      [=========================]
Querying                      [=========================]
Refreshing software list      [=========================]
There are no updates available at this time.
$ pkcon update tiff
More than one package matches:
1. tiff-4.0.2-1.9.1.i586 [repo-oss]
2. tiff-4.0.2-1.12.1.x86_64 [repo-update]
3. tiff-4.0.2-1.12.1.i586 [repo-update]
4. tiff-4.0.2-1.9.1.x86_64 [repo-oss]
5. tiff-4.0.2-1.12.1.source [repo-update]
Please choose the correct package: 4
Simulating update             [=========================]
Waiting in queue              [=========================]
Starting                      [=========================]
Resolving dependencies        [=========================]
Installing updates            [=========================]
Installing packages           [=========================]
Updating packages             [=========================]
Waiting in queue              [=========================]
Waiting for authentication    [=========================]
Waiting in queue              [=========================]
Starting                      [=========================]
Resolving dependencies        [=========================]
Installing updates            [=========================]
Downloading packages          [=========================]
Installing packages           [=========================]
$ pkcon get-updates
Getting updates               [=========================]
Waiting in queue              [=========================]
Starting                      [=========================]
Querying                      [=========================]
Refreshing software list      [=========================]
Security        openSUSE-2013-29-1.noarch                       update for tiff

cu
Ludwig

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  (o_   Ludwig Nussel
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