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perl-5.42.2
⭐ Starred 2013 / shasum
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

shasum - Print or Check SHA Checksums

SYNOPSIS

Usage: shasum [OPTION]... [FILE]...
Print or check SHA checksums.
With no FILE, or when FILE is -, read standard input.

  -a, --algorithm   1 (default), 224, 256, 384, 512, 512224, 512256
  -b, --binary      read in binary mode
  -c, --check       read SHA sums from the FILEs and check them
      --tag         create a BSD-style checksum
  -t, --text        read in text mode (default)
  -U, --UNIVERSAL   read in Universal Newlines mode
                        produces same digest on Windows/Unix/Mac
  -0, --01          read in BITS mode
                        ASCII '0' interpreted as 0-bit,
                        ASCII '1' interpreted as 1-bit,
                        all other characters ignored

The following five options are useful only when verifying checksums:
      --ignore-missing  don't fail or report status for missing files
  -q, --quiet           don't print OK for each successfully verified file
  -s, --status          don't output anything, status code shows success
      --strict          exit non-zero for improperly formatted checksum lines
  -w, --warn            warn about improperly formatted checksum lines

  -h, --help        display this help and exit
  -v, --version     output version information and exit

When verifying SHA-512/224 or SHA-512/256 checksums, indicate the
algorithm explicitly using the -a option, e.g.

  shasum -a 512224 -c checksumfile

The sums are computed as described in FIPS PUB 180-4.  When checking,
the input should be a former output of this program.  The default
mode is to print a line with checksum, a character indicating type
(`*' for binary, ` ' for text, `U' for UNIVERSAL, `^' for BITS),
and name for each FILE.  The line starts with a `\' character if the
FILE name contains either newlines or backslashes, which are then
replaced by the two-character sequences `\n' and `\\' respectively.

Report shasum bugs to mshelor@cpan.org

DESCRIPTION

Running shasum is often the quickest way to compute SHA message digests. The user simply feeds data to the script through files or standard input, and then collects the results from standard output.

The following command shows how to compute digests for typical inputs such as the NIST test vector "abc":

perl -e "print qq(abc)" | shasum

Or, if you want to use SHA-256 instead of the default SHA-1, simply say:

perl -e "print qq(abc)" | shasum -a 256

Since shasum mimics the behavior of the combined GNU sha1sum, sha224sum, sha256sum, sha384sum, and sha512sum programs, you can install this script as a convenient drop-in replacement.

Unlike the GNU programs, shasum encompasses the full SHA standard by allowing partial-byte inputs. This is accomplished through the BITS option (-0). The following example computes the SHA-224 digest of the 7-bit message 0001100:

perl -e "print qq(0001100)" | shasum -0 -a 224

AUTHOR

Copyright (C) 2003-2023 Mark Shelor <mshelor@cpan.org>.

SEE ALSO

shasum is implemented using the Perl module Digest::SHA.