Security Advisories (8)
CVE-2020-12723 (2020-06-05)

regcomp.c in Perl before 5.30.3 allows a buffer overflow via a crafted regular expression because of recursive S_study_chunk calls.

CVE-2020-10878 (2020-06-05)

Perl before 5.30.3 has an integer overflow related to mishandling of a "PL_regkind[OP(n)] == NOTHING" situation. A crafted regular expression could lead to malformed bytecode with a possibility of instruction injection.

CVE-2020-10543 (2020-06-05)

Perl before 5.30.3 on 32-bit platforms allows a heap-based buffer overflow because nested regular expression quantifiers have an integer overflow.

CVE-2018-6798 (2018-04-17)

An issue was discovered in Perl 5.22 through 5.26. Matching a crafted locale dependent regular expression can cause a heap-based buffer over-read and potentially information disclosure.

CVE-2023-47100

In Perl before 5.38.2, S_parse_uniprop_string in regcomp.c can write to unallocated space because a property name associated with a \p{...} regular expression construct is mishandled. The earliest affected version is 5.30.0.

CVE-2024-56406 (2025-04-13)

A heap buffer overflow vulnerability was discovered in Perl. When there are non-ASCII bytes in the left-hand-side of the `tr` operator, `S_do_trans_invmap` can overflow the destination pointer `d`.    $ perl -e '$_ = "\x{FF}" x 1000000; tr/\xFF/\x{100}/;'    Segmentation fault (core dumped) It is believed that this vulnerability can enable Denial of Service and possibly Code Execution attacks on platforms that lack sufficient defenses.

CVE-2025-40909 (2025-05-30)

Perl threads have a working directory race condition where file operations may target unintended paths. If a directory handle is open at thread creation, the process-wide current working directory is temporarily changed in order to clone that handle for the new thread, which is visible from any third (or more) thread already running. This may lead to unintended operations such as loading code or accessing files from unexpected locations, which a local attacker may be able to exploit. The bug was introduced in commit 11a11ecf4bea72b17d250cfb43c897be1341861e and released in Perl version 5.13.6

CVE-2023-47039 (2023-10-30)

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.

NAME

FindBin - Locate directory of original perl script

SYNOPSIS

use FindBin;
use lib "$FindBin::Bin/../lib";

or

use FindBin qw($Bin);
use lib "$Bin/../lib";

DESCRIPTION

Locates the full path to the script bin directory to allow the use of paths relative to the bin directory.

This allows a user to setup a directory tree for some software with directories <root>/bin and <root>/lib, and then the above example will allow the use of modules in the lib directory without knowing where the software tree is installed.

If perl is invoked using the -e option or the perl script is read from STDIN then FindBin sets both $Bin and $RealBin to the current directory.

EXPORTABLE VARIABLES

$Bin         - path to bin directory from where script was invoked
$Script      - basename of script from which perl was invoked
$RealBin     - $Bin with all links resolved
$RealScript  - $Script with all links resolved

KNOWN ISSUES

If there are two modules using FindBin from different directories under the same interpreter, this won't work. Since FindBin uses a BEGIN block, it'll be executed only once, and only the first caller will get it right. This is a problem under mod_perl and other persistent Perl environments, where you shouldn't use this module. Which also means that you should avoid using FindBin in modules that you plan to put on CPAN. To make sure that FindBin will work is to call the again function:

use FindBin;
FindBin::again(); # or FindBin->again;

In former versions of FindBin there was no again function. The workaround was to force the BEGIN block to be executed again:

delete $INC{'FindBin.pm'};
require FindBin;

AUTHORS

FindBin is supported as part of the core perl distribution. Please send bug reports to <perlbug@perl.org> using the perlbug program included with perl.

Graham Barr <gbarr@pobox.com> Nick Ing-Simmons <nik@tiuk.ti.com>

COPYRIGHT

Copyright (c) 1995 Graham Barr & Nick Ing-Simmons. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.