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perl-5.42.2
⭐ Starred 2013 / OS2::ExtAttr
Security Advisories (3)
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.

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.

NAME

OS2::ExtAttr - Perl access to extended attributes.

SYNOPSIS

use OS2::ExtAttr;
tie %ea, 'OS2::ExtAttr', 'my.file';
print $ea{eaname};
$ea{myfield} = 'value';

untie %ea;

DESCRIPTION

The package provides low-level and high-level interface to Extended Attributes under OS/2.

High-level interface: tie

The only argument of tie() is a file name, or an open file handle.

Note that all the changes of the tied hash happen in core, to propagate it to disk the tied hash should be untie()ed or should go out of scope. Alternatively, one may use the low-level update method on the corresponding object. Example:

tied(%hash)->update;

Note also that setting/getting EA flag is not supported by the high-level interface, one should use the low-level interface instead. To use it on a tied hash one needs undocumented way to find eas give the tied hash.

Low-level interface

Two low-level methods are supported by the objects: copy() and update(). The copy() takes one argument: the name of a file to copy the attributes to, or an opened file handle. update() takes no arguments, and is discussed above.

Three convenience functions are provided:

value($eas, $key)
add($eas, $key, $value [, $flag])
replace($eas, $key, $value [, $flag])

The default value for flag is 0.

In addition, all the _ea_* and _ead_* functions defined in EMX library are supported, with leading _ea and _ead stripped.

AUTHOR

Ilya Zakharevich, ilya@math.ohio-state.edu

SEE ALSO

perl(1).