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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

feature - Perl pragma to enable new features

SYNOPSIS

    use feature qw(switch say);
    given ($foo) {
	when (1)	  { say "\$foo == 1" }
	when ([2,3])	  { say "\$foo == 2 || \$foo == 3" }
	when (/^a[bc]d$/) { say "\$foo eq 'abd' || \$foo eq 'acd'" }
	when ($_ > 100)   { say "\$foo > 100" }
	default		  { say "None of the above" }
    }

    use feature ':5.10'; # loads all features available in perl 5.10

DESCRIPTION

It is usually impossible to add new syntax to Perl without breaking some existing programs. This pragma provides a way to minimize that risk. New syntactic constructs, or new semantic meanings to older constructs, can be enabled by use feature 'foo', and will be parsed only when the appropriate feature pragma is in scope.

Lexical effect

Like other pragmas (use strict, for example), features have a lexical effect. use feature qw(foo) will only make the feature "foo" available from that point to the end of the enclosing block.

{
    use feature 'say';
    say "say is available here";
}
print "But not here.\n";

no feature

Features can also be turned off by using no feature "foo". This too has lexical effect.

use feature 'say';
say "say is available here";
{
    no feature 'say';
    print "But not here.\n";
}
say "Yet it is here.";

no feature with no features specified will turn off all features.

The 'switch' feature

use feature 'switch' tells the compiler to enable the Perl 6 given/when construct.

See "Switch statements" in perlsyn for details.

The 'say' feature

use feature 'say' tells the compiler to enable the Perl 6 say function.

See "say" in perlfunc for details.

the 'state' feature

use feature 'state' tells the compiler to enable state variables.

See "Persistent Private Variables" in perlsub for details.

the 'unicode_strings' feature

use feature 'unicode_strings' tells the compiler to use Unicode semantics in all string operations executed within its scope (unless they are also within the scope of either use locale or use bytes). The same applies to all regular expressions compiled within the scope, even if executed outside it.

no feature 'unicode_strings' tells the compiler to use the traditional Perl semantics wherein the native character set semantics is used unless it is clear to Perl that Unicode is desired. This can lead to some surprises when the behavior suddenly changes. (See "The "Unicode Bug"" in perlunicode for details.) For this reason, if you are potentially using Unicode in your program, the use feature 'unicode_strings' subpragma is strongly recommended.

This subpragma is available starting with Perl 5.11.3, but was not fully implemented until 5.13.8.

FEATURE BUNDLES

It's possible to load a whole slew of features in one go, using a feature bundle. The name of a feature bundle is prefixed with a colon, to distinguish it from an actual feature. At present, the only feature bundle is use feature ":5.10" which is equivalent to use feature qw(switch say state).

Specifying sub-versions such as the 0 in 5.10.0 in feature bundles has no effect: feature bundles are guaranteed to be the same for all sub-versions.

IMPLICIT LOADING

There are two ways to load the feature pragma implicitly :

  • By using the -E switch on the command-line instead of -e. It enables all available features in the main compilation unit (that is, the one-liner.)

  • By requiring explicitly a minimal Perl version number for your program, with the use VERSION construct, and when the version is higher than or equal to 5.10.0. That is,

    use 5.10.0;

    will do an implicit

    use feature ':5.10';

    and so on. Note how the trailing sub-version is automatically stripped from the version.

    But to avoid portability warnings (see "use" in perlfunc), you may prefer:

    use 5.010;

    with the same effect.