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perl-5.14.3
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Security Advisories (18)
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-2018-6913 (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-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-2013-1667 (2013-03-14)

The rehash mechanism in Perl 5.8.2 through 5.16.x allows context-dependent attackers to cause a denial of service (memory consumption and crash) via a crafted hash key.

CVE-2012-5195 (2012-12-18)

Heap-based buffer overflow in the Perl_repeatcpy function in util.c in Perl 5.12.x before 5.12.5, 5.14.x before 5.14.3, and 5.15.x before 15.15.5 allows context-dependent attackers to cause a denial of service (memory consumption and crash) or possibly execute arbitrary code via the 'x' string repeat operator.

CVE-2016-2381 (2016-04-08)

Perl might allow context-dependent attackers to bypass the taint protection mechanism in a child process via duplicate environment variables in envp.

CVE-2013-7422 (2015-08-16)

Integer underflow in regcomp.c in Perl before 5.20, as used in Apple OS X before 10.10.5 and other products, allows context-dependent attackers to execute arbitrary code or cause a denial of service (application crash) via a long digit string associated with an invalid backreference within a regular expression.

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-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.

CVE-2015-8608 (2017-02-07)

The VDir::MapPathA and VDir::MapPathW functions in Perl 5.22 allow remote attackers to cause a denial of service (out-of-bounds read) and possibly execute arbitrary code via a crafted (1) drive letter or (2) pInName argument.

NAME

open - perl pragma to set default PerlIO layers for input and output

SYNOPSIS

use open IN  => ":crlf", OUT => ":bytes";
use open OUT => ':utf8';
use open IO  => ":encoding(iso-8859-7)";

use open IO  => ':locale';

use open ':encoding(utf8)';
use open ':locale';
use open ':encoding(iso-8859-7)';

use open ':std';

DESCRIPTION

Full-fledged support for I/O layers is now implemented provided Perl is configured to use PerlIO as its IO system (which is now the default).

The open pragma serves as one of the interfaces to declare default "layers" (also known as "disciplines") for all I/O. Any two-argument open(), readpipe() (aka qx//) and similar operators found within the lexical scope of this pragma will use the declared defaults. Even three-argument opens may be affected by this pragma when they don't specify IO layers in MODE.

With the IN subpragma you can declare the default layers of input streams, and with the OUT subpragma you can declare the default layers of output streams. With the IO subpragma you can control both input and output streams simultaneously.

If you have a legacy encoding, you can use the :encoding(...) tag.

If you want to set your encoding layers based on your locale environment variables, you can use the :locale tag. For example:

$ENV{LANG} = 'ru_RU.KOI8-R';
# the :locale will probe the locale environment variables like LANG
use open OUT => ':locale';
open(O, ">koi8");
print O chr(0x430); # Unicode CYRILLIC SMALL LETTER A = KOI8-R 0xc1
close O;
open(I, "<koi8");
printf "%#x\n", ord(<I>), "\n"; # this should print 0xc1
close I;

These are equivalent

use open ':encoding(utf8)';
use open IO => ':encoding(utf8)';

as are these

use open ':locale';
use open IO => ':locale';

and these

use open ':encoding(iso-8859-7)';
use open IO => ':encoding(iso-8859-7)';

The matching of encoding names is loose: case does not matter, and many encodings have several aliases. See Encode::Supported for details and the list of supported locales.

When open() is given an explicit list of layers (with the three-arg syntax), they override the list declared using this pragma.

The :std subpragma on its own has no effect, but if combined with the :utf8 or :encoding subpragmas, it converts the standard filehandles (STDIN, STDOUT, STDERR) to comply with encoding selected for input/output handles. For example, if both input and out are chosen to be :encoding(utf8), a :std will mean that STDIN, STDOUT, and STDERR are also in :encoding(utf8). On the other hand, if only output is chosen to be in :encoding(koi8r), a :std will cause only the STDOUT and STDERR to be in koi8r. The :locale subpragma implicitly turns on :std.

The logic of :locale is described in full in encoding, but in short it is first trying nl_langinfo(CODESET) and then guessing from the LC_ALL and LANG locale environment variables.

Directory handles may also support PerlIO layers in the future.

NONPERLIO FUNCTIONALITY

If Perl is not built to use PerlIO as its IO system then only the two pseudo-layers :bytes and :crlf are available.

The :bytes layer corresponds to "binary mode" and the :crlf layer corresponds to "text mode" on platforms that distinguish between the two modes when opening files (which is many DOS-like platforms, including Windows). These two layers are no-ops on platforms where binmode() is a no-op, but perform their functions everywhere if PerlIO is enabled.

IMPLEMENTATION DETAILS

There is a class method in PerlIO::Layer find which is implemented as XS code. It is called by import to validate the layers:

PerlIO::Layer::->find("perlio")

The return value (if defined) is a Perl object, of class PerlIO::Layer which is created by the C code in perlio.c. As yet there is nothing useful you can do with the object at the perl level.

SEE ALSO

"binmode" in perlfunc, "open" in perlfunc, perlunicode, PerlIO, encoding