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perl-5.41.3
⭐ Starred 2013 / CPAN::Meta::History::Meta_1_1
Security Advisories (8)
CVE-2024-56406 (2025-04-13)

A heap buffer overflow vulnerability was discovered in Perl. Release branches 5.34, 5.36, 5.38 and 5.40 are affected, including development versions from 5.33.1 through 5.41.10. 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-2026-13221 (2026-07-13)

Perl versions before 5.40.5-RC1, from 5.41.0 before 5.42.3-RC1, from 5.43.0 before 5.43.10 produce silently incorrect regular expression matches when an alternation of more than 65535 fixed string branches is compiled into a trie in Perl_study_chunk. When such branches are combined into a trie, the delta between the first branch and the shared tail is stored in a 16-bit field. A branch count above 65535 overflows the field, and the trie's match decision table is truncated with no warning or error. A pattern of this shape produces false positive matches (matching strings it should not) and false negative matches (failing to match strings it should). When such a pattern gates an access or filtering decision, the result is wrong.

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-2026-8376 (2026-05-25)

Perl versions before 5.40.5-RC1, from 5.41.0 before 5.42.3-RC1, from 5.43.0 before 5.43.11 have a heap buffer overflow when compiling regular expressions with a repeated fixed string on 32-bit builds. Perl_study_chunk in regcomp_study.c checked the size of the joined substring buffer in characters rather than bytes. For a quantified fixed substring with a large minimum count, the byte length mincount * l could overflow SSize_t, producing an undersized SvGROW allocation; the subsequent copy writes past the end of the buffer. A caller that compiles an attacker-controlled regular expression on a 32-bit perl build triggers a heap buffer overflow at compile time.

CVE-2026-15534 (2026-08-09)

Perl versions through 5.45.1 have out-of-bounds heap reads and writes during regular expression matching via an undersized superlinear cache in S_regmatch. The regex engine's superlinear cache holds one bit per subject position for each participating WHILEM node, so the bit count is the subject length plus one times the number of nodes. Nothing checks that product for positive overflow of the signed 32-bit count: a 286331153 byte subject matched against a pattern with 15 participating nodes stores the count as 14, leaving a two byte cache. The cache is then indexed from the real match position and node number, so reads go past the end of the allocation, and on failure CACHEsayNO sets a bit past it. A caller that matches an attacker controlled subject of this size against a pattern of this shape can crash the process or corrupt heap memory.

CVE-2026-19487 (2026-08-13)

Perl versions from 5.9.4 before 5.41.9 produce incorrect regular expression match results when a stale failure flag ends the Aho-Corasick prescan early in S_find_byclass. The prescan walks the subject for positions where the full pattern could match, and the engine tries it from the leftmost one recorded. A failing transition sets the failed flag, and a later successful transition does not clear it, so the prescan reads the stale flag as a failure and stops before it can record a candidate that starts earlier. It takes a subject where one candidate is recorded and a later character then forces a fallback through a fail link that succeeds. Example: "ABCDE" =~ m/ABCF|BCDE|C/; # matches C at offset 2, not BCDE "ABCDE" =~ m/ABCF|BCDE|C(G)/; # no match, BCDE missed An alternation like this can miss input it should match, or match it on the wrong branch, so an access or filtering decision made from the result can be wrong.

CVE-2026-4176 (2026-03-29)

Perl versions from 5.9.4 before 5.40.4-RC1, from 5.41.0 before 5.42.2-RC1, from 5.43.0 before 5.43.9 contain a vulnerable version of Compress::Raw::Zlib. Compress::Raw::Zlib is included in the Perl package as a dual-life core module, and is vulnerable to CVE-2026-3381 due to a vendored version of zlib which has several vulnerabilities, including CVE-2026-27171. The bundled Compress::Raw::Zlib was updated to version 2.221 in Perl blead commit c75ae9cc164205e1b6d6dbd57bd2c65c8593fe94.

CVE-2026-57432 (2026-07-13)

Perl versions before 5.40.5-RC1, from 5.41.0 before 5.42.3-RC1, from 5.43.0 before 5.43.11 have an integer overflow in S_measure_struct leading to an out-of-bounds heap read in pack and unpack. S_measure_struct adds each item's size times its repeat count to a running total with no overflow check, so a large repeat count in a pack or unpack template wraps the signed SSize_t total negative. The @, X, and x position codes then guard their moves with a signed length comparison that passes when the length is negative, advancing the buffer pointer out of bounds. A template derived from untrusted input can read heap memory past the buffer and return it to the caller.

NAME

CPAN::Meta::History::Meta_1_1 - Version 1.1 metadata specification for META.yml

PREFACE

This is a historical copy of the version 1.1 specification for META.yml files, copyright by Ken Williams and licensed under the same terms as Perl itself.

Modifications from the original:

  • Conversion from the original HTML to POD format

  • Include list of valid licenses from Module::Build 0.18 rather than linking to the module, with minor updates to text and links to reflect versions at the time of publication.

  • Fixed some dead links to point to active resources.

DESCRIPTION

This document describes version 1.1 of the META.yml specification.

The META.yml file describes important properties of contributed Perl distributions such as the ones found on CPAN. It is typically created by tools like Module::Build and ExtUtils::MakeMaker.

The fields in the META.yml file are meant to be helpful to people maintaining module collections (like CPAN), for people writing installation tools (like CPAN or CPANPLUS), or just people who want to know some stuff about a distribution before downloading it and starting to install it.

Format

META.yml files are written in the YAML format. The reasons we chose YAML instead of, say, XML or Data::Dumper are discussed in this thread on the MakeMaker mailing list.

The first line of a META.yml file should be a valid YAML document header like "--- #YAML:1.0"

Fields

The rest of the META.yml file is one big YAML mapping, whose keys are described here.

name

Example: Module-Build

The name of the distribution. Often created by taking the "main module" in the distribution and changing "::" to "-". Sometimes it's completely different, however, as in the case of the libwww-perl distribution.

version

Example: 0.16

The version of the distribution to which the META.yml file refers. This is a mandatory field.

The version is essentially an arbitrary string, but must be only ASCII characters, and strongly should be of the format integer-dot-digit-digit, i.e. 25.57, optionally followed by underscore-digit-digit, i.e. 25.57_04.

The standard tools that deal with module distribution (PAUSE, CPAN, etc.) form an identifier for each distribution by joining the 'name' and 'version' attributes with a dash (-) character. Tools who are prepared to deal with distributions that have no version numbers generally omit the dash as well.

license

Example: perl

a descriptive term for the licenses ... not authoritative, but must be consistent with licensure statements in the READMEs, documentation, etc.

The license under which this distribution may be used and redistributed.

Must be one of the following licenses:

perl

The distribution may be copied and redistributed under the same terms as perl itself (this is by far the most common licensing option for modules on CPAN). This is a dual license, in which the user may choose between either the GPL version 1 or the Artistic version 1 license.

gpl

The distribution is distributed under the terms of the GNU General Public License version 2 (http://opensource.org/licenses/GPL-2.0).

lgpl

The distribution is distributed under the terms of the GNU Lesser General Public License version 2 (http://opensource.org/licenses/LGPL-2.1).

artistic

The distribution is licensed under the Artistic License version 1, as specified by the Artistic file in the standard perl distribution (http://opensource.org/licenses/Artistic-Perl-1.0).

bsd

The distribution is licensed under the BSD 3-Clause License (http://opensource.org/licenses/BSD-3-Clause).

open_source

The distribution is licensed under some other Open Source Initiative-approved license listed at http://www.opensource.org/licenses/.

unrestricted

The distribution is licensed under a license that is not approved by www.opensource.org but that allows distribution without restrictions.

restrictive

The distribution may not be redistributed without special permission from the author and/or copyright holder.

license_uri

This should contain a URI where the exact terms of the license may be found.

(change "unrestricted" to "redistributable"?)

distribution_type

Example: module

What kind of stuff is contained in this distribution. Most things on CPAN are modules (which can also mean a collection of modules), but some things are scripts.

This field is basically meaningless, and tools (like Module::Build or MakeMaker) will likely stop generating it in the future.

private

WTF is going on here?

index_ignore: any application that indexes the contents of distributions (PAUSE, search.cpan.org) ought to ignore the items (packages, files, directories, namespace hierarchies).

requires

Example:

Data::Dumper: 0
File::Find: 1.03

A YAML mapping indicating the Perl modules this distribution requires for proper operation. The keys are the module names, and the values are version specifications as described in the documentation for Module::Build's "requires" parameter.

Note: the exact nature of the fancy specifications like ">= 1.2, != 1.5, < 2.0" is subject to change. Advance notice will be given here. The simple specifications like "1.2" will not change in format.

recommends

Example:

Data::Dumper: 0
File::Find: 1.03

A YAML mapping indicating the Perl modules this distribution recommends for enhanced operation.

build_requires

Example:

Data::Dumper: 0
File::Find: 1.03

A YAML mapping indicating the Perl modules required for building and/or testing of this distribution. These dependencies are not required after the module is installed.

conflicts

Example:

Data::Dumper: 0
File::Find: 1.03

A YAML mapping indicating the Perl modules that cannot be installed while this distribution is installed. This is a pretty uncommon situation.

- possibly separate out test-time prereqs, complications include: can tests be meaningfully preserved for later running? are test-time prereqs in addition to build-time, or exclusive?

- make official location for installed *distributions*, which can contain tests, etc.

dynamic_config

Example: 0

A boolean flag indicating whether a Build.PL or Makefile.PL (or similar) must be executed, or whether this module can be built, tested and installed solely from consulting its metadata file. The main reason to set this to a true value if that your module performs some dynamic configuration (asking questions, sensing the environment, etc.) as part of its build/install process.

Currently Module::Build doesn't actually do anything with this flag - it's probably going to be up to higher-level tools like CPAN.pm to do something useful with it. It can potentially bring lots of security, packaging, and convenience improvements.

generated_by

Example: Module::Build version 0.16

Indicates the tool that was used to create this META.yml file. It's good form to include both the name of the tool and its version, but this field is essentially opaque, at least for the moment.

Ingy's suggestions

short_description

add as field, containing abstract, maximum 80 characters, suggested minimum 40 characters

description

long version of abstract, should add?

maturity

alpha, beta, gamma, mature, stable

author_id, owner_id
categorization, keyword, chapter_id
URL for further information

could default to search.cpan.org on PAUSE

namespaces

can be specified for single elements by prepending dotted-form, i.e. "com.example.my_application.my_property". Default namespace for META.yml is probably "org.cpan.meta_author" or something. Precedent for this is Apple's Carbon namespaces, I think.

History

  • March 14, 2003 (Pi day) - created version 1.0 of this document.

  • May 8, 2003 - added the "dynamic_config" field, which was missing from the initial version.