/ 
perl-5.22.3
⭐ Starred 2013
/ fields
Security Advisories (19)
CVE-2016-6185 (2016-08-02)

The XSLoader::load method in XSLoader in Perl does not properly locate .so files when called in a string eval, which might allow local users to execute arbitrary code via a Trojan horse library under the current working directory.

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-2018-6797 (2018-04-17)

An issue was discovered in Perl 5.18 through 5.26. A crafted regular expression can cause a heap-based buffer overflow, with control over the bytes written.

CVE-2018-6913 (2018-04-17)

Heap-based buffer overflow in the pack function in Perl before 5.26.2 allows context-dependent attackers to execute arbitrary code via a large item count.

CVE-2018-18314 (2018-12-07)

Perl before 5.26.3 has a buffer overflow via a crafted regular expression that triggers invalid write operations.

CVE-2018-18313 (2018-12-07)

Perl before 5.26.3 has a buffer over-read via a crafted regular expression that triggers disclosure of sensitive information from process memory.

CVE-2018-18312 (2018-12-05)

Perl before 5.26.3 and 5.28.0 before 5.28.1 has a buffer overflow via a crafted regular expression that triggers invalid write operations.

CVE-2018-18311 (2018-12-07)

Perl before 5.26.3 and 5.28.x before 5.28.1 has a buffer overflow via a crafted regular expression that triggers invalid write operations.

CVE-2017-12883 (2017-09-19)

Buffer overflow in the S_grok_bslash_N function in regcomp.c in Perl 5 before 5.24.3-RC1 and 5.26.x before 5.26.1-RC1 allows remote attackers to disclose sensitive information or cause a denial of service (application crash) via a crafted regular expression with an invalid '\\N{U+...}' escape.

CVE-2017-12837 (2017-09-19)

Heap-based buffer overflow in the S_regatom function in regcomp.c in Perl 5 before 5.24.3-RC1 and 5.26.x before 5.26.1-RC1 allows remote attackers to cause a denial of service (out-of-bounds write) via a regular expression with a '\\N{}' escape and the case-insensitive modifier.

CVE-2015-8853 (2016-05-25)

The (1) S_reghop3, (2) S_reghop4, and (3) S_reghopmaybe3 functions in regexec.c in Perl before 5.24.0 allow context-dependent attackers to cause a denial of service (infinite loop) via crafted utf-8 data, as demonstrated by "a\x80."

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.

CVE-2016-1238 (2016-08-02)

(1) cpan/Archive-Tar/bin/ptar, (2) cpan/Archive-Tar/bin/ptardiff, (3) cpan/Archive-Tar/bin/ptargrep, (4) cpan/CPAN/scripts/cpan, (5) cpan/Digest-SHA/shasum, (6) cpan/Encode/bin/enc2xs, (7) cpan/Encode/bin/encguess, (8) cpan/Encode/bin/piconv, (9) cpan/Encode/bin/ucmlint, (10) cpan/Encode/bin/unidump, (11) cpan/ExtUtils-MakeMaker/bin/instmodsh, (12) cpan/IO-Compress/bin/zipdetails, (13) cpan/JSON-PP/bin/json_pp, (14) cpan/Test-Harness/bin/prove, (15) dist/ExtUtils-ParseXS/lib/ExtUtils/xsubpp, (16) dist/Module-CoreList/corelist, (17) ext/Pod-Html/bin/pod2html, (18) utils/c2ph.PL, (19) utils/h2ph.PL, (20) utils/h2xs.PL, (21) utils/libnetcfg.PL, (22) utils/perlbug.PL, (23) utils/perldoc.PL, (24) utils/perlivp.PL, and (25) utils/splain.PL in Perl 5.x before 5.22.3-RC2 and 5.24 before 5.24.1-RC2 do not properly remove . (period) characters from the end of the includes directory array, which might allow local users to gain privileges via a Trojan horse module under the current working directory.

NAME

fields - compile-time class fields

SYNOPSIS

{
    package Foo;
    use fields qw(foo bar _Foo_private);
    sub new {
        my Foo $self = shift;
        unless (ref $self) {
            $self = fields::new($self);
            $self->{_Foo_private} = "this is Foo's secret";
        }
        $self->{foo} = 10;
        $self->{bar} = 20;
        return $self;
    }
}

my $var = Foo->new;
$var->{foo} = 42;

# this will generate a run-time error
$var->{zap} = 42;

# this will generate a compile-time error
my Foo $foo = Foo->new;
$foo->{zap} = 24;

# subclassing
{
    package Bar;
    use base 'Foo';
    use fields qw(baz _Bar_private);        # not shared with Foo
    sub new {
        my $class = shift;
        my $self = fields::new($class);
        $self->SUPER::new();                # init base fields
        $self->{baz} = 10;                  # init own fields
        $self->{_Bar_private} = "this is Bar's secret";
        return $self;
    }
}

DESCRIPTION

The fields pragma enables compile-time and run-time verified class fields.

NOTE: The current implementation keeps the declared fields in the %FIELDS hash of the calling package, but this may change in future versions. Do not update the %FIELDS hash directly, because it must be created at compile-time for it to be fully useful, as is done by this pragma.

If a typed lexical variable (my Class $var) holding a reference is used to access a hash element and a package with the same name as the type has declared class fields using this pragma, then the hash key is verified at compile time. If the variables are not typed, access is only checked at run time.

The related base pragma will combine fields from base classes and any fields declared using the fields pragma. This enables field inheritance to work properly. Inherited fields can be overridden but will generate a warning if warnings are enabled.

Only valid for Perl 5.8.x and earlier: Field names that start with an underscore character are made private to the class and are not visible to subclasses.

Also, in Perl 5.8.x and earlier, this pragma uses pseudo-hashes, the effect being that you can have objects with named fields which are as compact and as fast arrays to access, as long as the objects are accessed through properly typed variables.

The following functions are supported:

new

fields::new() creates and blesses a hash comprised of the fields declared using the fields pragma into the specified class. It is the recommended way to construct a fields-based object.

This makes it possible to write a constructor like this:

package Critter::Sounds;
use fields qw(cat dog bird);

sub new {
    my $self = shift;
    $self = fields::new($self) unless ref $self;
    $self->{cat} = 'meow';                      # scalar element
    @$self{'dog','bird'} = ('bark','tweet');    # slice
    return $self;
}
phash

This function only works in Perl 5.8.x and earlier. Pseudo-hashes were removed from Perl as of 5.10. Consider using restricted hashes or fields::new() instead (which itself uses restricted hashes under 5.10+). See Hash::Util. Using fields::phash() under 5.10 or higher will cause an error.

fields::phash() can be used to create and initialize a plain (unblessed) pseudo-hash. This function should always be used instead of creating pseudo-hashes directly.

If the first argument is a reference to an array, the pseudo-hash will be created with keys from that array. If a second argument is supplied, it must also be a reference to an array whose elements will be used as the values. If the second array contains less elements than the first, the trailing elements of the pseudo-hash will not be initialized. This makes it particularly useful for creating a pseudo-hash from subroutine arguments:

sub dogtag {
   my $tag = fields::phash([qw(name rank ser_num)], [@_]);
}

fields::phash() also accepts a list of key-value pairs that will be used to construct the pseudo hash. Examples:

my $tag = fields::phash(name => "Joe",
                        rank => "captain",
                        ser_num => 42);

my $pseudohash = fields::phash(%args);

SEE ALSO

base, Hash::Util