/ 
perl-5.23.3
⭐ Starred 2013
/ O
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

O - Generic interface to Perl Compiler backends

SYNOPSIS

perl -MO=[-q,]Backend[,OPTIONS] foo.pl

DESCRIPTION

This is the module that is used as a frontend to the Perl Compiler.

If you pass the -q option to the module, then the STDOUT filehandle will be redirected into the variable $O::BEGIN_output during compilation. This has the effect that any output printed to STDOUT by BEGIN blocks or use'd modules will be stored in this variable rather than printed. It's useful with those backends which produce output themselves (Deparse, Concise etc), so that their output is not confused with that generated by the code being compiled.

The -qq option behaves like -q, except that it also closes STDERR after deparsing has finished. This suppresses the "Syntax OK" message normally produced by perl.

CONVENTIONS

Most compiler backends use the following conventions: OPTIONS consists of a comma-separated list of words (no white-space). The -v option usually puts the backend into verbose mode. The -ofile option generates output to file instead of stdout. The -D option followed by various letters turns on various internal debugging flags. See the documentation for the desired backend (named B::Backend for the example above) to find out about that backend.

IMPLEMENTATION

This section is only necessary for those who want to write a compiler backend module that can be used via this module.

The command-line mentioned in the SYNOPSIS section corresponds to the Perl code

use O ("Backend", OPTIONS);

The O::import function loads the appropriate B::Backend module and calls its compile function, passing it OPTIONS. That function is expected to return a sub reference which we'll call CALLBACK. Next, the "compile-only" flag is switched on (equivalent to the command-line option -c) and a CHECK block is registered which calls CALLBACK. Thus the main Perl program mentioned on the command-line is read in, parsed and compiled into internal syntax tree form. Since the -c flag is set, the program does not start running (excepting BEGIN blocks of course) but the CALLBACK function registered by the compiler backend is called.

In summary, a compiler backend module should be called "B::Foo" for some foo and live in the appropriate directory for that name. It should define a function called compile. When the user types

perl -MO=Foo,OPTIONS foo.pl

that function is called and is passed those OPTIONS (split on commas). It should return a sub ref to the main compilation function. After the user's program is loaded and parsed, that returned sub ref is invoked which can then go ahead and do the compilation, usually by making use of the B module's functionality.

BUGS

The -q and -qq options don't work correctly if perl isn't compiled with PerlIO support : STDOUT will be closed instead of being redirected to $O::BEGIN_output.

AUTHOR

Malcolm Beattie, mbeattie@sable.ox.ac.uk