I have a rather involved perl script that reads an email from STDIN using MIME::Parser and a few other libraries to split apart an email into its different components for writing to a database. The problem is that it now appears some emails have subjects that span two lines, and MIME::Parser doesn't appear to be able to process it properly. 
use strict;
use Advisory;
use MIME::Parser;
use MIME::Entity;
use MIME::WordDecoder;
use MIME::Tools;
use MIME::Decoder;
use Email::MIME;

my $parser = MIME::Parser->new;                                       
+                                                                     
+                                                                     
+ 
$parser->extract_uuencode(1);
$parser->extract_nested_messages(1);
$parser->output_to_core(1);

my $buf;
while(<STDIN> ){
        $buf .= $_;
}
my @mailData = split( '\n', $buf);
my $entity = $parser->parse_data($buf);
my $subject = $entity->head->get('Subject');
my $from = $entity->head->get('From');
my $AdvDate = $entity->head->get('Date');

my $linecount = 0;
my $inadvis = 0;
foreach my $line (@mailData) {
        chomp($line);

        if ($line =~ m/^Description:/) {
           $startShort = "true";
           next;
        }
        if ($linecount lt 5 && $startShort eq "true") {
           $shortDesc .= $line . " ";
           $linecount++;
        }
        #print "line: $line\n";
        # MGASA-2018-0463 - Updated roundcubemail packages fix securit
+y vulnerability & bugs
        # MGASA-2018-0439 - Updated ansible package fixes security vul
+nerabilities
        #print "line: $line\n";
        if ($line =~ m/MGASA-(\d+)-(\d+) - Updated (.*) package/) {
           $pkgname = $3;
           $subject = "Mageia $1-$2: $3 security update";
           $inadvis = 1;
        }
        # MGASA-2019-0151 - Virtualbox 6.0.6 fixes security vulnerabil
+ities
        elsif ($line =~ m/MGASA-(\d+)-(\d+) - (.*) (.*) fixes security
+ vulnerabilities/) {
           $pkgname = $3;
           $subject = "Mageia $1-$2: $3 security update";
           $inadvis = 1;
        }
        # [updates-announce] MGASA-2023-0355: New chromium-browser-sta
+ble 120.0.6099.129 fixes bugs and vulnerabilities
        elsif ($line =~ m/MGASA-(\d+)-(\d+): New (.*) (.*) fixes bugs 
+and/) {
           $pkgname = $3;
           $subject = "Mageia $1-$2: $3 security update";
           $inadvis = 1;
        }
        if ($inadvis == 1) {
           $advisory .= $line . "\n";
        }

}

[download]
The example subject I'm working with that spans two lines is as follows: 
Subject: [updates-announce] MGASA-2023-0355: New chromium-browser-stab
+le
 120.0.6099.129 fixes bugs and vulnerabilities

[download]
I've put the entire mbox email in a paste here

https://pastebin.com/LRs9J4pd

Any ideas greatly appreciated.

In reply to MIME::Parser and multi-line subjects by gossamer

Title:
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