PERL5343DELTA(1) Perl Programmers Reference Guide PERL5343DELTA(1)
NAME
perl5343delta - what is new for perl v5.34.3
DESCRIPTION
This document describes differences between the 5.34.1 release and the
5.34.3 release. Please note: This document ignores Perl 5.34.2, a
broken release which existed for a couple of days only.
If you are upgrading from an earlier release such as 5.34.0, first read
perl5341delta, which describes differences between 5.34.0 and 5.34.1.
Security
This release fixes the following security issues.
CVE-2023-47038 - Write past buffer end via illegal user-defined Unicode
property
This vulnerability was reported directly to the Perl security team by
Nathan Mills "the.true.nathan.mills@gmail.com".
A crafted regular expression when compiled by perl 5.30.0 through 5.38.0
can cause a one-byte attacker controlled buffer overflow in a heap
allocated buffer.
CVE-2023-47039 - Perl for Windows binary hijacking vulnerability
This vulnerability was reported to the Intel Product Security Incident
Response Team (PSIRT) by GitHub user ycdxsb
<https://github.com/ycdxsb/WindowsPrivilegeEscalation>. PSIRT then
reported it to the Perl security team.
Perl for Windows relies on the system path environment variable to find
the shell ("cmd.exe"). When running an executable which uses Windows
Perl interpreter, Perl attempts to find and execute "cmd.exe" within the
operating system. However, due to path search order issues, Perl
initially looks for cmd.exe in the current working directory.
An attacker with limited privileges can exploit this behavior by placing
"cmd.exe" in locations with weak permissions, such as "C:\ProgramData".
By doing so, when an administrator attempts to use this executable from
these compromised locations, arbitrary code can be executed.
Acknowledgements
Perl 5.34.3 represents approximately 1 month of development since Perl
5.34.1 and contains approximately 3,700 lines of changes across 40 files
from 4 authors.
Excluding auto-generated files, documentation and release tools, there
were approximately 2,800 lines of changes to 9 .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 5.34.3:
Karl Williamson, Paul Evans, 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://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.
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.
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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