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/f9af01426038e29d9578825a0cd3626946ab08c7
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-2026-9538
  Distribution:  Archive-Tar
  Versions:  before 3.10

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

  Archive::Tar versions before 3.10 for Perl allow memory exhaustion via
  attacker controlled entry size field in tar header

  Description
  -----------
  Archive::Tar versions before 3.10 for Perl allow memory exhaustion via
  attacker controlled entry size field in tar header.

  _read_tar() reads each entry's payload with $handle->read($$data,
  $block), where $block is derived from the entry's 12-byte size field in
  the tar header with no upper bound on that value.

  A crafted header declaring a multi-gigabyte size causes Perl to
  allocate a scalar of that size.

[0] https://lists.security.metacpan.org/cve-announce/msg/40396448/

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