man > perl5281delta(1)

PERL5281DELTA(1)                  Perl Programmers Reference Guide                  PERL5281DELTA(1)

NAME
       perl5281delta - what is new for perl v5.28.1

DESCRIPTION
       This document describes differences between the 5.28.0 release and the 5.28.1 release.

       If you are upgrading from an earlier release such as 5.26.0, first read perl5280delta, which
       describes differences between 5.26.0 and 5.28.0.

Security
   [CVE-2018-18311] Integer overflow leading to buffer overflow and segmentation fault
       Integer arithmetic in Perl_my_setenv() could wrap when the combined length of the environment
       variable name and value exceeded around 0x7fffffff.  This could lead to writing beyond the
       end of an allocated buffer with attacker supplied data.

       [GH #16560] <https://github.com/Perl/perl5/issues/16560>

   [CVE-2018-18312] Heap-buffer-overflow write in S_regatom (regcomp.c)
       A crafted regular expression could cause heap-buffer-overflow write during compilation,
       potentially allowing arbitrary code execution.

       [GH #16649] <https://github.com/Perl/perl5/issues/16649>

Incompatible Changes
       There are no changes intentionally incompatible with 5.28.0.  If any exist, they are bugs,
       and we request that you submit a report.  See "Reporting Bugs" below.

Modules and Pragmata
   Updated Modules and Pragmata
       •   Module::CoreList has been upgraded from version 5.20180622 to 5.20181129_28.

Selected Bug Fixes
       •   Perl 5.28 introduced an index() optimization when comparing to -1 (or indirectly, e.g. >=
           0).   When  this  optimization  was  triggered inside a "when" clause it caused a warning
           ("Argument %s isn't numeric in smart match").  This has  now  been  fixed.   [GH  #16626]
           <https://github.com/Perl/perl5/issues/16626>

       •   Matching of decimal digits in script runs, introduced in Perl 5.28, had a bug that led to
           "1\N{THAI  DIGIT  FIVE}"  matching "/^(*sr:\d+)$/" when it should not.  This has now been
           fixed.

       •   The  new  in-place  editing  code  no  longer  leaks  directory  handles.   [GH   #16602]
           <https://github.com/Perl/perl5/issues/16602>

Acknowledgements
       Perl  5.28.1  represents approximately 5 months of development since Perl 5.28.0 and contains
       approximately 6,100 lines of changes across 44 files from 12 authors.

       Excluding auto-generated files, documentation and release tools, there were approximately 700
       lines of changes to 12 .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 5.28.1:

       Aaron Crane, Abigail, Chris 'BinGOs' Williams,  Dagfinn  Ilmari  Mannsåker,  David  Mitchell,
       James E Keenan, John SJ Anderson, Karen Etheridge, Karl Williamson, Sawyer X, Steve Hay, Tony
       Cook.

       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.

       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://rt.perl.org/>  .  There may also be information at <http://www.perl.org/> , the Perl
       Home Page.

       If you believe you have an unreported bug, please run the perlbug program included with  your
       release.  Be sure to trim your bug down to a tiny but sufficient test case.  Your bug report,
       along  with  the  output of "perl -V", will be sent off to perlbug AT perl.org to be analysed by
       the Perl porting team.

       If the bug you are reporting has security implications which make it inappropriate to send to
       a publicly archived mailing list, then see "SECURITY VULNERABILITY  CONTACT  INFORMATION"  in
       perlsec for details of how to report the issue.

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.

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.

perl v5.38.2                                 2026-08-18                             PERL5281DELTA(1)