package libpng12-0 1.2.54-1ubuntu1 failed to install/upgrade: trying to overwrite shared '/usr/share/doc/libpng12-0/changelog.Debian.gz', which is different from other instances of package libpng12-0:amd64

[Nasser Pasha]

 /var/cache/apt/archives/libpng12-0_1.2.54-1ubuntu1.1_amd64.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)

ProblemType: Package
DistroRelease: Ubuntu 16.04
Package: libpng12-0 1.2.54-1ubuntu1
ProcVersionSignature: Ubuntu 4.15.0-70.79~16.04.1-generic 4.15.18
Uname: Linux 4.15.0-70-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.21
AptOrdering:
 libpng12-0: Install
 libpng12-0: Configure
 libpng12-0: Configure
 NULL: ConfigurePending
Architecture: amd64
Date: Fri Nov 29 08:19:09 2019
Dependencies:
 gcc-6-base 6.0.1-0ubuntu1
 libc6 2.23-0ubuntu11
 libgcc1 1:6.0.1-0ubuntu1
 zlib1g 1:1.2.8.dfsg-2ubuntu4.1
DpkgTerminalLog:
 Preparing to unpack .../libpng12-0_1.2.54-1ubuntu1.1_amd64.deb ...
 Unpacking libpng12-0:amd64 (1.2.54-1ubuntu1.1) over (1.2.54-1ubuntu1) ...
 dpkg: error processing archive /var/cache/apt/archives/libpng12-0_1.2.54-1ubuntu1.1_amd64.deb (--unpack):
  trying to overwrite shared '/usr/share/doc/libpng12-0/changelog.Debian.gz', which is different from other instances of package libpng12-0:amd64
DuplicateSignature:
 package:libpng12-0:1.2.54-1ubuntu1
 Unpacking libpng12-0:amd64 (1.2.54-1ubuntu1.1) over (1.2.54-1ubuntu1) ...
 dpkg: error processing archive /var/cache/apt/archives/libpng12-0_1.2.54-1ubuntu1.1_amd64.deb (--unpack):
  trying to overwrite shared '/usr/share/doc/libpng12-0/changelog.Debian.gz', which is different from other instances of package libpng12-0:amd64
ErrorMessage: trying to overwrite shared '/usr/share/doc/libpng12-0/changelog.Debian.gz', which is different from other instances of package libpng12-0:amd64
InstallationDate: Installed on 2019-11-27 (1 days ago)
InstallationMedia: Ubuntu 16.04.6 LTS "Xenial Xerus" - Release amd64 (20190227)
RelatedPackageVersions:
 dpkg 1.18.4ubuntu1.6
 apt 1.2.32
SourcePackage: libpng
Title: package libpng12-0 1.2.54-1ubuntu1 failed to install/upgrade: trying to overwrite shared '/usr/share/doc/libpng12-0/changelog.Debian.gz', which is different from other instances of package libpng12-0:amd64
UpgradeStatus: No upgrade log present (probably fresh install)

[Eduardo Barretto (ebarretto)]

Thanks for taking the time to report this bug and helping to make Ubuntu better. We appreciate the difficulties you are facing, but this appears to be a "regular" (non-security) bug. I have unmarked it as a security issue since this bug does not show evidence of allowing attackers to cross privilege boundaries nor directly cause loss of data/privacy. Please feel free to report any other bugs you may find.

[Apport retracing service (apport)]

Thank you for taking the time to report this crash and helping to make this software better. This particular crash has already been reported and is a duplicate of bug #1799215, so is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Please continue to report any other bugs you may find.