sudo apt-get install --reinstall pepperflashplugin-nonfree
Reading package lists... Done
Building dependency tree       
Reading state information... Done
0 upgraded, 0 newly installed, 1 reinstalled, 0 to remove and 30 not upgraded.
Need to get 0 B/11.1 kB of archives.
After this operation, 0 B of additional disk space will be used.
(Reading database ... 314355 files and directories currently installed.)
Preparing to unpack .../pepperflashplugin-nonfree_1.7ubuntu1_amd64.deb ...
Unpacking pepperflashplugin-nonfree (1.7ubuntu1) over (1.7ubuntu1) ...
Setting up pepperflashplugin-nonfree (1.7ubuntu1) ...
ERROR: failed to retrieve status information from google : W: Can't drop privileges for downloading as file './var/lib/apt/lists/partial/dl.google.com_linux_chrome_deb_dists_stable_InRelease' couldn't be accessed by user '_apt'. - pkgAcquire::Run (13: Permission denied)
More information might be available at:
  http://wiki.debian.org/PepperFlashPlayer