Security Advisories (12)
CVE-2023-47038 (2023-10-30)

A crafted regular expression when compiled by perl 5.30.0 through 5.38.0 can cause a one attacker controlled byte buffer overflow in a heap allocated buffer

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-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-2026-4176 (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 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-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-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-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

Dumpvalue - provides screen dump of Perl data.

SYNOPSIS

use Dumpvalue;
my $dumper = Dumpvalue->new;
$dumper->set(globPrint => 1);
$dumper->dumpValue(\*::);
$dumper->dumpvars('main');
my $dump = $dumper->stringify($some_value);

DESCRIPTION

Creation

A new dumper is created by a call

$d = Dumpvalue->new(option1 => value1, option2 => value2)

Recognized options:

arrayDepth, hashDepth

Print only first N elements of arrays and hashes. If false, prints all the elements.

compactDump, veryCompact

Change style of array and hash dump. If true, short array may be printed on one line.

globPrint

Whether to print contents of globs.

dumpDBFiles

Dump arrays holding contents of debugged files.

dumpPackages

Dump symbol tables of packages.

dumpReused

Dump contents of "reused" addresses.

tick, quoteHighBit, printUndef

Change style of string dump. Default value of tick is auto, one can enable either double-quotish dump, or single-quotish by setting it to " or '. By default, characters with high bit set are printed as is. If quoteHighBit is set, they will be quoted.

usageOnly

rudimentary per-package memory usage dump. If set, dumpvars calculates total size of strings in variables in the package.

unctrl

Changes the style of printout of strings. Possible values are unctrl and quote.

subdump

Whether to try to find the subroutine name given the reference.

bareStringify

Whether to write the non-overloaded form of the stringify-overloaded objects.

quoteHighBit

Whether to print chars with high bit set in binary or "as is".

stopDbSignal

Whether to abort printing if debugger signal flag is raised.

Later in the life of the object the methods may be queries with get() method and set() method (which accept multiple arguments).

Methods

dumpValue
$dumper->dumpValue($value);
$dumper->dumpValue([$value1, $value2]);

Prints a dump to the currently selected filehandle.

dumpValues
$dumper->dumpValues($value1, $value2);

Same as $dumper->dumpValue([$value1, $value2]);.

stringify
my $dump = $dumper->stringify($value [,$noticks] );

Returns the dump of a single scalar without printing. If the second argument is true, the return value does not contain enclosing ticks. Does not handle data structures.

dumpvars
$dumper->dumpvars('my_package');
$dumper->dumpvars('my_package', 'foo', '~bar$', '!......');

The optional arguments are considered as literal strings unless they start with ~ or !, in which case they are interpreted as regular expressions (possibly negated).

The second example prints entries with names foo, and also entries with names which ends on bar, or are shorter than 5 chars.

set_quote
$d->set_quote('"');

Sets tick and unctrl options to suitable values for printout with the given quote char. Possible values are auto, ' and ".

set_unctrl
$d->set_unctrl('unctrl');

Sets unctrl option with checking for an invalid argument. Possible values are unctrl and quote.

compactDump
$d->compactDump(1);

Sets compactDump option. If the value is 1, sets to a reasonable big number.

veryCompact
$d->veryCompact(1);

Sets compactDump and veryCompact options simultaneously.

set
$d->set(option1 => value1, option2 => value2);
get
@values = $d->get('option1', 'option2');