/ 
perl-5.27.11
⭐ Starred 2013 / Pod::Simple::HTML
Security Advisories (13)
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-2026-57432 (2026-07-13)

Perl versions through 5.43.10 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.

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-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-2026-13221 (2026-07-13)

Perl versions through 5.43.9 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-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-2026-8376 (2026-05-25)

Perl versions through 5.43.10 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-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-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-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.

NAME

Pod::Simple::HTML - convert Pod to HTML

SYNOPSIS

perl -MPod::Simple::HTML -e Pod::Simple::HTML::go thingy.pod

DESCRIPTION

This class is for making an HTML rendering of a Pod document.

This is a subclass of Pod::Simple::PullParser and inherits all its methods (and options).

Note that if you want to do a batch conversion of a lot of Pod documents to HTML, you should see the module Pod::Simple::HTMLBatch.

CALLING FROM THE COMMAND LINE

TODO

perl -MPod::Simple::HTML -e Pod::Simple::HTML::go Thing.pod Thing.html

CALLING FROM PERL

Minimal code

use Pod::Simple::HTML;
my $p = Pod::Simple::HTML->new;
$p->output_string(\my $html);
$p->parse_file('path/to/Module/Name.pm');
open my $out, '>', 'out.html' or die "Cannot open 'out.html': $!\n";
print $out $html;

More detailed example

use Pod::Simple::HTML;

Set the content type:

$Pod::Simple::HTML::Content_decl =  q{<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" >};

my $p = Pod::Simple::HTML->new;

Include a single javascript source:

$p->html_javascript('http://abc.com/a.js');

Or insert multiple javascript source in the header (or for that matter include anything, thought this is not recommended)

$p->html_javascript('
    <script type="text/javascript" src="http://abc.com/b.js"></script>
    <script type="text/javascript" src="http://abc.com/c.js"></script>');

Include a single css source in the header:

$p->html_css('/style.css');

or insert multiple css sources:

$p->html_css('
    <link rel="stylesheet" type="text/css" title="pod_stylesheet" href="http://remote.server.com/jquery.css">
    <link rel="stylesheet" type="text/css" title="pod_stylesheet" href="/style.css">');

Tell the parser where should the output go. In this case it will be placed in the $html variable:

my $html;
$p->output_string(\$html);

Parse and process a file with pod in it:

$p->parse_file('path/to/Module/Name.pm');

METHODS

TODO all (most?) accessorized methods

The following variables need to be set before the call to the ->new constructor.

Set the string that is included before the opening <html> tag:

  $Pod::Simple::HTML::Doctype_decl = qq{<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" 
	 "http://www.w3.org/TR/html4/loose.dtd">\n};

Set the content-type in the HTML head: (defaults to ISO-8859-1)

$Pod::Simple::HTML::Content_decl =  q{<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" >};

Set the value that will be embedded in the opening tags of F, C tags and verbatim text. F maps to <em>, C maps to <code>, Verbatim text maps to <pre> (Computerese defaults to "")

$Pod::Simple::HTML::Computerese =  ' class="some_class_name';

html_css

html_javascript

title_prefix

title_postfix

html_header_before_title

This includes everything before the <title> opening tag including the Document type and including the opening <title> tag. The following call will set it to be a simple HTML file:

$p->html_header_before_title('<html><head><title>');

top_anchor

By default Pod::Simple::HTML adds a dummy anchor at the top of the HTML. You can change it by calling

$p->top_anchor('<a name="zz" >');

html_h_level

Normally =head1 will become <h1>, =head2 will become <h2> etc. Using the html_h_level method will change these levels setting the h level of =head1 tags:

$p->html_h_level(3);

Will make sure that =head1 will become <h3> and =head2 will become <h4> etc...

index

Set it to some true value if you want to have an index (in reality a table of contents) to be added at the top of the generated HTML.

$p->index(1);

html_header_after_title

Includes the closing tag of </title> and through the rest of the head till the opening of the body

$p->html_header_after_title('</title>...</head><body id="my_id">');

The very end of the document:

$p->html_footer( qq[\n<!-- end doc -->\n\n</body></html>\n] );

SUBCLASSING

Can use any of the methods described above but for further customization one needs to override some of the methods:

package My::Pod;
use strict;
use warnings;

use base 'Pod::Simple::HTML';

# needs to return a URL string such
# http://some.other.com/page.html
# #anchor_in_the_same_file
# /internal/ref.html
sub do_pod_link {
  # My::Pod object and Pod::Simple::PullParserStartToken object
  my ($self, $link) = @_;

  say $link->tagname;          # will be L for links
  say $link->attr('to');       # 
  say $link->attr('type');     # will be 'pod' always
  say $link->attr('section');

  # Links local to our web site
  if ($link->tagname eq 'L' and $link->attr('type') eq 'pod') {
    my $to = $link->attr('to');
    if ($to =~ /^Padre::/) {
        $to =~ s{::}{/}g;
        return "/docs/Padre/$to.html";
    }
  }

  # all other links are generated by the parent class
  my $ret = $self->SUPER::do_pod_link($link);
  return $ret;
}

1;

Meanwhile in script.pl:

use My::Pod;

my $p = My::Pod->new;

my $html;
$p->output_string(\$html);
$p->parse_file('path/to/Module/Name.pm');
open my $out, '>', 'out.html' or die;
print $out $html;

TODO

maybe override do_beginning do_end

SEE ALSO

Pod::Simple, Pod::Simple::HTMLBatch

TODO: a corpus of sample Pod input and HTML output? Or common idioms?

SUPPORT

Questions or discussion about POD and Pod::Simple should be sent to the pod-people@perl.org mail list. Send an empty email to pod-people-subscribe@perl.org to subscribe.

This module is managed in an open GitHub repository, https://github.com/perl-pod/pod-simple/. Feel free to fork and contribute, or to clone git://github.com/perl-pod/pod-simple.git and send patches!

Patches against Pod::Simple are welcome. Please send bug reports to <bug-pod-simple@rt.cpan.org>.

COPYRIGHT AND DISCLAIMERS

Copyright (c) 2002-2004 Sean M. Burke.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

This program is distributed in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose.

ACKNOWLEDGEMENTS

Thanks to Hurricane Electric for permission to use its Linux man pages online site for man page links.

Thanks to search.cpan.org for permission to use the site for Perl module links.

AUTHOR

Pod::Simple was created by Sean M. Burke <sburke@cpan.org>. But don't bother him, he's retired.

Pod::Simple is maintained by:

  • Allison Randal allison@perl.org

  • Hans Dieter Pearcey hdp@cpan.org

  • David E. Wheeler dwheeler@cpan.org