/ 
perl-5.43.8
⭐ Starred 2013 / locale
Security Advisories (4)
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-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-2026-57432 (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.

NAME

locale - Perl pragma to use or avoid POSIX locales for built-in operations

SYNOPSIS

my @x1 = sort @y;      # Native-platform/Unicode code point sort order
{
    use locale;
    my @x2 = sort @y;  # Locale-defined sort order
}
my @x3 = sort @y;      # Native-platform/Unicode code point sort order
                       # again

# Parameters to the pragma are to work around deficiencies in locale
# handling that have since been fixed, and hence these are likely no
# longer useful
use locale qw(:ctype :collate);    # Only use the locale for character
                                   # classification (\w, \d, etc.), and
                                   # for string comparison operations
                                   # like '$a le $b' and sorting.
use locale ':not_characters';      # Use the locale for everything but
                                   # character classification and string
                                   # comparison operations

use locale ':!numeric';            # Use the locale for everything but
                                   # numeric-related operations
use locale ':not_numeric';         # Same

no locale;             # Turn off locale handling for the remainder of
                       # the scope.

DESCRIPTION

This pragma tells the compiler to enable (or disable) the use of POSIX locales for built-in operations (for example, LC_CTYPE for regular expressions, LC_COLLATE for string comparison, and LC_NUMERIC for number formatting). Each use locale or no locale affects statements to the end of the enclosing BLOCK.

The pragma is documented as part of perllocale.