Package: perl
Version: 5.40.1-6
Severity: important
Tags: security upstream
X-Debbugs-Cc: carnil@debian.org
Forwarded: https://github.com/jib/archive-tar-new/commit/17c873492a05eddc0de18c1485e0b2cccd5a9158
Control: found -1 5.32.1-4
Control: found -1 5.36.0-1
Control: found -1 5.42.2-1

The following vulnerability was published[0] for Archive-Tar (bundled with perl):

  CVE ID:  CVE-2026-42496
  Distribution:  Archive-Tar
  Versions:  before 3.08

  MetaCPAN:  https://metacpan.org/dist/Archive-Tar
  VCS Repo:  https://github.com/jib/archive-tar-new

  Archive::Tar versions before 3.08 for Perl extract symlinks with
  attacker controlled targets outside the extraction directory

  Description
  -----------
  Archive::Tar versions before 3.08 for Perl extract symlinks with
  attacker controlled targets outside the extraction directory.

  _make_special_file() passes the tar header's linkname to symlink()
  without validating it against absolute paths or .. segments. The
  secure-extract mode check that guards regular file extraction does not
  cover the symlink target.

  A subsequent open through the extracted name reads or writes the
  attacker chosen path.

[0] https://lists.security.metacpan.org/cve-announce/msg/40396459/

I'm postponing fixes for CVE-2026-42496, CVE-2026-42497, and CVE-2026-9538
in Archive-Tar.

These are rather intertwined, and backporting them onto older versions
is pretty much the same thing as upgrading the whole module.

Also there's a regression fix in Archive-Tar 3.12 and I want to wait a bit
to see if others surface.

Upstream plans to include the fixes in point releases for 5.42 and 5.40,
as discussed in https://github.com/Perl/perl5/issues/24445 . Let's see
what they do with this first.

Hi Niko,

Sounds good, thanks for the update on those!

Regards,
Salvatore