PERL5385DELTA(1perl)

📦
version 5.44.0 · 2 versions
, in arch rolling

💖 PERL5385DELTA 💖

okay bestie, this is the tea on perl5385delta — the manual page from the Perl Programmers Reference Guide that spills everything new in Perl v5.38.5. It's giving release-notes energy, it's giving changelog, and honestly? We're obsessed. 🫶

🌸 NAME 🌸

perl5385delta — what is new for perl v5.38.5 ✨

🦋 DESCRIPTION 🦋

So this doc is literally just describing the differences between the 5.38.4 release and the 5.38.5 release. That's it, that's the whole vibe. 💅

Real talk though: if you're upgrading from something earlier — like, say, 5.38.3 — you have to do your homework first and read perl5384delta, which goes over the differences between 5.38.3 and 5.38.4. No skipping steps, okay? 😌

🔒 Security 🔒

🚨 [CVE-2025-40909] Perl threads have a working directory race condition where file operations may target unintended paths 🚨

ngl this one is serious serious, so pay attention bestie.

Perl thread cloning had a working directory race condition where file operations may target unintended paths. That's the whole problem. Because of it, Perl 5.38 will no longer chdir to each handle.

💀 A race condition where your file operations hit the wrong paths is exactly the kind of chaos we do not want in our lives. This is a real security fix, not a cute little tweak.

This problem was discovered by Vincent Lefèvre via [GH #23010](https://github.com/Perl/perl5/issues/23010) and assigned [CVE-2025-40909](https://lists.security.metacpan.org/cve-announce/msg/30017499/) by the [CPAN Security Group](https://security.metacpan.org/).

Fixes were provided via [GH #23019](https://github.com/Perl/perl5/pull/23019) and [GH #23361](https://github.com/Perl/perl5/pull/23361). Slay. 🔥

🙈 Incompatible Changes 🙈

Literally nothing, bestie. There are no changes intentionally incompatible with 5.38.4. Periodt.

If any do exist, they're bugs, and we are asking you so nicely to submit a report. Go see "Reporting Bugs" down below. 👇

🎀 Modules and Pragmata 🎀

✨ Updated Modules and Pragmata ✨

  • Module::CoreList has been upgraded from version 5.20250413_38 to 5.20250803_38. glow up 💅

📚 Documentation 📚

🌈 Changes to Existing Documentation 🌈

We have attempted to update the documentation to reflect the changes listed in this document. If you find any we have missed, open an issue at <https://github.com/Perl/perl5/issues>. We're literally begging you to snitch (affectionately). 🥺

🧪 Testing 🧪

Tests were added and changed to reflect the other additions and changes in this release. (This is the unglamorous main-character work that keeps everything from falling apart. Respect.) 👑

💜 Acknowledgements 💜

Perl 5.38.5 represents approximately 4 months of development since Perl 5.38.4 and contains approximately 3,300 lines of changes across 46 files from 8 authors.

Excluding auto-generated files, documentation and release tools, there were approximately 1,100 lines of changes to 7 .pm, .t, .c and .h files.

Perl continues to flourish into its fourth decade thanks to a vibrant community of users and developers. 🦋 The following people are known to have contributed the improvements that became Perl 5.38.5:

  • James E Keenan
  • Karen Etheridge
  • Leon Timmermans
  • Lukas Mai
  • Philippe Bruhat (BooK)
  • Richard Leach
  • Steve Hay
  • Thibault Duponchelle

The list above is almost certainly incomplete as it is automatically generated from version control history. In particular, it does not include the names of the (very much appreciated) contributors who reported issues to the Perl bug tracker. And like, they deserve their flowers too. 💐

Many of the changes included in this version originated in the CPAN modules included in Perl's core. We're grateful to the entire CPAN community for helping Perl to flourish. 🫶

For a more complete list of all of Perl's historical contributors, please see the AUTHORS file in the Perl source distribution.

🐛 Reporting Bugs 🐛

If you find what you think is a bug, you might check the perl bug database at <https://github.com/Perl/perl5/issues>. There may also be information at <http://www.perl.org/>, the Perl Home Page. 👀

If you believe you have an unreported bug, please open an issue at <https://github.com/Perl/perl5/issues>. Be sure to trim your bug down to a tiny but sufficient test case. (Tiny but sufficient. That's the assignment. ✂️)

If the bug you are reporting has security implications which make it inappropriate to send to a public issue tracker, then see "SECURITY VULNERABILITY CONTACT INFORMATION" in perlsec for details of how to report the issue. Please do NOT just post it publicly, bestie, that's the one time you keep the secret. 🤫

🌟 Give Thanks 🌟

If you wish to thank the Perl 5 Porters for the work we had done in Perl 5, you can do so by running the perlthanks program:

perlthanks

This will send an email to the Perl 5 Porters list with your show of thanks. Look at you being a good person. We love to see it. 💖

👀 SEE ALSO 👀

  • The Changes file for an explanation of how to view exhaustive details on what changed.
  • The INSTALL file for how to build Perl.
  • The README file for general stuff.
  • The Artistic and Copying files for copyright information.

okay that's the whole page, you're officially caught up 🎀 and for the sign-off vibe check: this was perl v5.44.0, dated 2026-10-17, filed under PERL5385DELTA(1perl). go forth and run your upgrades, bestie 💅✨

📦 where this page comes from