[Bug 2043711] Re: Open3.pm tries to run code in /tmp when updating ubuntu-drivers-common

[Andrew J. Caines]

@vorlon, Thank you for your considered response. I concur that this is
not a vulnerability in the Ubuntu perl package.

While I do not disagree with any of the points you make, the fact
remains that processes running as root created a file directly in /tmp
not using a safe *mktemp* process and later ran the code in that file.
The risks of doing this are sufficiently well understood, as the
preferable alternatives.

Given that that this quite vanilla Ubuntu system and that this behaviour
was only observed as a result of the reasonable and fairly common
configuration of mounting `/tmp` with *noexec* and did so while running
updates in a fully supported manner, i.e. with *Software Updater*, this
remains a bug with a directly associated security risk. That is to say -
as you expressed it - this comes from an Ubuntu package, though I don't
know which.

Do you recommend that I do anything other than change the Package to
"debconf" and Status to "New"?


@juliank, *apt-utils* is installed.

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https://bugs.launchpad.net/bugs/2043711

Title:
  Open3.pm tries to run code in /tmp when updating ubuntu-drivers-common

Status in perl package in Ubuntu:
  Invalid

Bug description:
  During update of ubuntu-drivers-common:

    Can't exec "/tmp/ubuntu-drivers-common.config.55GJ8b": Permission denied at /usr/lib/x86_64-linux-gnu/perl-base/IPC/Open3.pm line 178, <GEN0> line 1.
  open2: exec of /tmp/ubuntu-drivers-common.config.55GJ8b configure 1:0.9.6.2~0.22.04.4 failed: Permission 
    denied at /usr/share/perl5/Debconf/ConfModule.pm line 59.
    Preconfiguring packages ...
    Can't exec "/tmp/ubuntu-drivers-common.config.uSPrCH": Permission denied at /usr/lib/x86_64-linux-gnu/perl-base/IPC/Open3.pm line 178, <GEN0> line 1.
    open2: exec of /tmp/ubuntu-drivers-common.config.uSPrCH configure 1:0.9.6.2~0.22.04.4 failed: Permission 
    denied at /usr/share/perl5/Debconf/ConfModule.pm line 59.

  /tmp is mounted with noexec because running code from /tmp has been a
  vulnerability vector for several decades, hence reporting this as a
  vulnerability in perl-base.

  This error did not appear to prevent the update of ubuntu-drivers-
  common and "dpkg --verify ubuntu-drivers-common" returns 0.

  ___________________________________________________________________________________________________________

  Attempting to use the package search on this form by clicking the 🔍
  created a modal in which there is an error

    Sorry, something went wrong with your search. We've recorded what
  happened, and we'll fix it as soon as possible. (Error ID:
  OOPS-c80f71590b02908a1187b9f743c53eac)

  which is repeated with any attempt to search for a package.

  ___________________________________________________________________________________________________________

  Submitting this form gives an error

    "perl-base" does not exist in Ubuntu. Please choose a different
  package. If you're unsure, please select "I don't know"

    $ dpkg -S /usr/lib/x86_64-linux-gnu/perl-base/IPC/Open3.pm
    perl-base: /usr/lib/x86_64-linux-gnu/perl-base/IPC/Open3.pm
    $ dpkg -l perl-base
    Desired=Unknown/Install/Remove/Purge/Hold
    | Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
    |/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
    ||/ Name           Version           Architecture Description
    +++-==============-=================-============-=============================>
    ii  perl-base      5.34.0-3ubuntu1.2 amd64        minimal Perl system

  Looks like a package to me. Nevertheless, using "Did you mean..."
  offers "perl".

  ProblemType: Bug
  DistroRelease: Ubuntu 22.04
  Package: perl-base 5.34.0-3ubuntu1.2
  ProcVersionSignature: Ubuntu 6.5.0-1007.7-oem 6.5.3
  Uname: Linux 6.5.0-1007-oem x86_64
  ApportVersion: 2.20.11-0ubuntu82.5
  Architecture: amd64
  CasperMD5CheckResult: unknown
  CurrentDesktop: ubuntu:GNOME
  Date: Thu Nov 16 10:08:48 2023
  InstallationDate: Installed on 2016-04-23 (2763 days ago)
  InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
  ProcEnviron:
   TERM=rxvt
   PATH=(custom, no user)
   XDG_RUNTIME_DIR=<set>
   LANG=en_US.UTF-8
   SHELL=/bin/bash
  SourcePackage: perl
  UpgradeStatus: Upgraded to jammy on 2022-08-19 (453 days ago)

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