apt-get upgrading security issue CVE-2016-1252

Very intersting response by an apt developer that I am going to study closer:

Please review this alternative sanity check:
Operating System Software and Updates - Kicksecure

1 Like

Good day,

Just checked it. Works as well.

Have a nice day,


1 Like

Thanks. Old workaround deprecated.

Operating System Software and Updates - Kicksecure

1 Like
  1. Is there anyway to verify non compromise yet for users who had already upgraded to version other than looking for “suspiciously extra long lines”? If not, how sure can one be of non compromise?

  2. If running Qubes OS, could other VMs possibly be compromised?

  3. What is best recommendation for user already upgraded to version

1 Like

There is none. And there will very much likely none in the foreseeable future. This is due to the the nature of malware. Detailed explanation:
Computer Security Education - Whonix

Practically, you cannot.

If the attacker used this exploit and then also was smart enough to have another exploit against xen and used that, then yes, also other VMs could possibly be comprised

Nothing. That is being discussed here:

That’s what I was afraid of.

Would you consider looking for “suspiciously extra long lines” and finding none, a reasonable confirmation of not having been compromised?
Following the directions, I didn’t see anything obviously suspicious.

Don’t believe I’m a target, just privacy conscious.
Going to put you on the spot. Sorry…
If it were you, what would you do in this situation?

No, because that is the first thing sophisticated malware would cover up after getting active on the system. And any attacker who exploited this vulnerability would certainly fit the definition of sophisticated.

Need to correct myself. As per Re: not getting compromised while applying apt-get upgrade for CVE-2016-1252 actually might be.

If you remember running apt-get update and you remember it not taking unusually long, that is if it did take as long as to download a ~ 1.3 GB file, then chances are very good you have not been compromised.

@ Patrick Thanks for the replies. Guess I was looking for professional confirmation of what I already knew.

Does anyone have thoughts as to the probability of malware being introduced because of this particular issue, especially considering many whonix users upgrade via exit nodes?

I am not aware of any reports of active attempts of exploitation of this bug in the wild. So for now targeted attacks only if anything. I can’t calculate a probability from that.

During manual apt-get update it would look sketchy to fetch a > 1 GB file. So not that unlikely to be spotted, I would speculate.

Most at risk seem systems using unattended upgrades. (No, Whonix does not use that.) (Specifically if these are distinguishable from manual apt-get updates - they could be - if they are running at expectable times. I don’t remember / haven’t checked this.)

Thank you Patrick for handling this well. Please let us know when debootstrap is safe for those of us who build our images.

1 Like

General usage of debootstrap [unrelated to Whonix]:
It will be safe out of the box after the next Debian point release when apt moves into jessie stable repository (not only in security.debian.org). Should be when Debian 8.7 is released.

Generally [unrelated to Whonix], running build processes using debootstrap followed by apt-get should be save when apt-get is visually watched. If it finishes usually quickly and does not download a > 1 GB file, no exploit attempt has happened. If it takes too long and is manually aborted, nothing can happen.

Before the Debian point release, to make Non-Qubes-Whonix safe without visually watching apt-get, a fix for Non-Qubes-Whonix build script similar to this one is still TODO:
Check for CVE-2016-1252 · marmarek/qubes-builder-debian@d755d2d · GitHub

Thanks Patrick. Will be interesting to see if there are any exploits reported because of this issue in the future.

Whonix git tag with CVE-2016-1252 workaround has been released. Building that should be safe. My build hasn’t finished yet, but I guess it’ll complete.

Downlandable Non-Qubes-Whonix are probably soon available.

Build succeeded. Testing and uploading is still todo.

1 Like

Upload finally done. Haven’t tested it myself yet. Release announcement coming later. https://download.whonix.org/

1 Like

Non-Qubes-Whonix release: Unfortunately I messed up including upgraded anon-ws-disable-stacked-tor for out of the box Tor Browser version > 6.5a6 support. So one still has to manually apt-get dist-upgraded and reboot (easiest) after installing Whonix. Will release it anyhow to get out of the box CVE-2016-1252 fix.


Some not so bright people at Debian want to enable unattended upgrades for all new installs…

1 Like

Good day,

Just tested, seems to work.

Have a nice day,


1 Like