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perl-5.45.1
⭐ Starred 2013 / DirHandle
Security Advisories (1)
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.

NAME

DirHandle - (obsolete) supply object methods for directory handles

SYNOPSIS

# recommended approach since Perl 5.6: do not use DirHandle
if (opendir my $d, '.') {
    while (readdir $d) { something($_); }
    rewind $d;
    while (readdir $d) { something_else($_); }
}

# how you would use this module if you were going to
use DirHandle;
if (my $d = DirHandle->new(".")) {
    while (defined($_ = $d->read)) { something($_); }
    $d->rewind;
    while (defined($_ = $d->read)) { something_else($_); }
}

DESCRIPTION

There is no reason to use this module nowadays.

The DirHandle method provide an alternative interface to the opendir(), closedir(), readdir(), and rewinddir() functions.

Up to Perl 5.5, opendir() could not autovivify a directory handle from undef, so using a lexical handle required using a function from Symbol to create an anonymous glob, which took a separate step. DirHandle encapsulates this, which allowed cleaner code than opendir(). Since Perl 5.6, opendir() alone has been all you need for lexical handles.