wheezy: apt fails to upgrade itself (segfaults)

As https://security-tracker.debian.org/tracker/CVE-2015-7547 is about to get fixed for wheezy, I tried to make sure apt-get update && apt-get upgrade have the latest info, however what could I do about the issue below?

Preparing to replace apt 0.9.7.9+deb7u2 (using .../apt_0.9.7.9+deb7u7_armel.deb) ...
Unpacking replacement apt ...
Processing triggers for man-db ...
Setting up apt (0.9.7.9+deb7u7) ...
Segmentation fault
Segmentation fault
dpkg: error processing apt (--configure):
subprocess installed post-installation script returned error exit status 139
Errors were encountered while processing:
apt
E: Sub-process /usr/bin/dpkg returned an error code (1)

I just tried to upgrade apt myself and I believe I was successful. Here's my output:

Preparing to replace apt 0.9.7.9+deb7u2 (using .../apt_0.9.7.9+deb7u7_armel.deb) ...
Unpacking replacement apt ...
Processing triggers for man-db ...
Setting up apt (0.9.7.9+deb7u7) ...
gpg: key B98321F9: "Squeeze Stable Release Key <debian-release@lists.debian.org>" not changed
gpg: key 473041FA: "Debian Archive Automatic Signing Key (6.0/squeeze) <ftpmaster@debian.org>" not changed
gpg: key 65FFB764: "Wheezy Stable Release Key <debian-release@lists.debian.org>" not changed
gpg: key 46925553: "Debian Archive Automatic Signing Key (7.0/wheezy) <ftpmaster@debian.org>" not changed
gpg: Total number processed: 4
gpg:              unchanged: 4

It looks like it runs apt-key update after it unpacks everything and that may be where the Segmentation faults are coming from. What happens if you try to run apt-key update?

Disclaimer: I'm about as far from an expert in this as I could be.

-JT

renojim Wrote:
-------------------------------------------------------
> I just tried to upgrade apt myself and I believe I
> was successful. Here's my output:

Preparing
> to replace apt 0.9.7.9+deb7u2 (using
> .../apt_0.9.7.9+deb7u7_armel.deb) ...
> Unpacking replacement apt ...
> Processing triggers for man-db ...
> Setting up apt (0.9.7.9+deb7u7) ...
> gpg: key ...
> gpg: Total number processed: 4
> gpg:              unchanged: 4

> It looks like it runs apt-key update after
> it unpacks everything and that may be where the
> Segmentation faults are coming from. What happens
> if you try to run apt-key update?

Segmentation fault
Segmentation fault

...expectedly.

Removing the following had no effect: /var/cache/apt/pkgcache.bin /var/cache/apt/srcpkgcache.bin
(even when followed by apt-get update && apt-get upgrade)

apt-get install aptitude
fails as above after "Setting up apt (0.9.7.9+deb7u7) ..."
so I can't get to that workaround either: aptitude reinstall apt-get (etc.)

I also get /usr/sbin/dpkg-reconfigure: apt is broken or not fully installed

Tried these to no avail:

dpkg -r apt
# it seems apt-get & apt-key aren't actually going away - though dpkg --contents shows them in the above package
dpkg -r apt-utils
dpkg -i /var/cache/apt/archives/apt_0.9.7.9+deb7u7_armel.deb
dpkg -i /var/cache/apt/archives/apt-utils_0.9.7.9+deb7u7_armel.deb
dpkg-reconfigure libapt-pkg4.12
dpkg-reconfigure libapt-inst1.5
dpkg-reconfigure gnupg
dpkg-reconfigure gpgv

So maybe the apt-key binary is corrupted? Can you run it with no parameters? It should print out some help.

-JT

renojim Wrote:
-------------------------------------------------------
> So maybe the apt-key binary is corrupted? Can you
> run it with no parameters? It should print out
> some help.

It does, it's rather gpg that segfaults even without parameters and after dpkg-reconfigure gnupg && dpkg-reconfigure gpgv (and I wonder if these are safe to reinstall without knocking SSH offline in the process, in case anything is shared in key management).

I was able to update both of them with apt-get with no problem, but I suppose that's not an option for you.

-JT