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perl-5.27.2
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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

less - perl pragma to request less of something

SYNOPSIS

use less 'CPU';

DESCRIPTION

This is a user-pragma. If you're very lucky some code you're using will know that you asked for less CPU usage or ram or fat or... we just can't know. Consult your documentation on everything you're currently using.

For general suggestions, try requesting CPU or memory.

use less 'memory';
use less 'CPU';
use less 'fat';

If you ask for nothing in particular, you'll be asking for less 'please'.

use less 'please';

FOR MODULE AUTHORS

less has been in the core as a "joke" module for ages now and it hasn't had any real way to communicating any information to anything. Thanks to Nicholas Clark we have user pragmas (see perlpragma) and now less can do something.

You can probably expect your users to be able to guess that they can request less CPU or memory or just "less" overall.

If the user didn't specify anything, it's interpreted as having used the please tag. It's up to you to make this useful.

# equivalent
use less;
use less 'please';

BOOLEAN = less->of( FEATURE )

The class method less->of( NAME ) returns a boolean to tell you whether your user requested less of something.

if ( less->of( 'CPU' ) ) {
    ...
}
elsif ( less->of( 'memory' ) ) {

}

FEATURES = less->of()

If you don't ask for any feature, you get the list of features that the user requested you to be nice to. This has the nice side effect that if you don't respect anything in particular then you can just ask for it and use it like a boolean.

if ( less->of ) {
    ...
}
else {
    ...
}

CAVEATS

This probably does nothing.
This works only on 5.10+

At least it's backwards compatible in not doing much.