PERL5263DELTA(1) Perl Programmers Reference Guide PERL5263DELTA(1)
NAME
perl5263delta - what is new for perl v5.26.3
DESCRIPTION
This document describes differences between the 5.26.2 release and the
5.26.3 release.
If you are upgrading from an earlier release such as 5.26.1, first read
perl5262delta, which describes differences between 5.26.1 and 5.26.2.
Security
[CVE-2018-12015] Directory traversal in module Archive::Tar
By default, Archive::Tar doesn't allow extracting files outside the
current working directory. However, this secure extraction mode could
be bypassed by putting a symlink and a regular file with the same name
into the tar file.
[GH #16580] <https://github.com/Perl/perl5/issues/16580> [cpan #125523]
<https://rt.cpan.org/Ticket/Display.html?id=125523>
[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>
[CVE-2018-18313] Heap-buffer-overflow read in S_grok_bslash_N (regcomp.c)
A crafted regular expression could cause heap-buffer-overflow read
during compilation, potentially leading to sensitive information being
leaked.
[GH #16554] <https://github.com/Perl/perl5/issues/16554>
[CVE-2018-18314] 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 #16041] <https://github.com/Perl/perl5/issues/16041>
Incompatible Changes
There are no changes intentionally incompatible with 5.26.2. 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
• Archive::Tar has been upgraded from version 2.24 to 2.24_01.
• Module::CoreList has been upgraded from version 5.20180414_26 to
5.20181129_26.
Diagnostics
The following additions or changes have been made to diagnostic output,
including warnings and fatal error messages. For the complete list of
diagnostic messages, see perldiag.
New Diagnostics
New Errors
• Unexpected ']' with no following ')' in (?[... in regex; marked by
<-- HERE in m/%s/
(F) While parsing an extended character class a ']' character was
encountered at a point in the definition where the only legal use of
']' is to close the character class definition as part of a '])',
you may have forgotten the close paren, or otherwise confused the
parser.
• Expecting close paren for nested extended charclass in regex; marked
by <-- HERE in m/%s/
(F) While parsing a nested extended character class like:
(?[ ... (?flags:(?[ ... ])) ... ])
^
we expected to see a close paren ')' (marked by ^) but did not.
• Expecting close paren for wrapper for nested extended charclass in
regex; marked by <-- HERE in m/%s/
(F) While parsing a nested extended character class like:
(?[ ... (?flags:(?[ ... ])) ... ])
^
we expected to see a close paren ')' (marked by ^) but did not.
Changes to Existing Diagnostics
• Syntax error in (?[...]) in regex; marked by <-- HERE in m/%s/
This fatal error message has been slightly expanded (from "Syntax
error in (?[...]) in regex m/%s/") for greater clarity.
Acknowledgements
Perl 5.26.3 represents approximately 8 months of development since Perl
5.26.2 and contains approximately 4,500 lines of changes across 51 files
from 15 authors.
Excluding auto-generated files, documentation and release tools, there
were approximately 770 lines of changes to 10 .pm, .t, .c and .h files.
Perl continues to flourish into its third decade thanks to a vibrant
community of users and developers. The following people are known to
have contributed the improvements that became Perl 5.26.3:
Aaron Crane, Abigail, Chris 'BinGOs' Williams, Dagfinn Ilmari Mannsåker,
David Mitchell, H.Merijn Brand, James E Keenan, John SJ Anderson, Karen
Etheridge, Karl Williamson, Sawyer X, Steve Hay, Todd Rinaldo, Tony
Cook, Yves Orton.
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@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.
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