Your regexen look reasonable enough to me. One way to keep your code a little cleaner when you have more than a couple of captures is with the use of the /x modifier and the new-ish named captures:

#!/usr/bin/env perl

use 5.014;
use warnings;

$_ = <DATA>; chomp;

/^  (?<mon>\w+)\s(?<dd>\d\d)
 \s (?<time>..:..:..) # could capture hh:mm:ss separately if need be
 \s (?<src>\d+\.\d+\.\d+\.\d+)
 # keep going with your sub-expressions
/x;

say "time: $+{time}  src: $+{src}";

__DATA__
May 20 18:57:27 1.23.25.5 %ASA-6-106100 a6 [local4.info] access-list M
+yaccess-Block permitted tcp outside/10.31.0.9(3803) -> inside/10.29.1
+0.91(4127) hit-cnt 1 300-second interval [0xa178b29d, 0x0]

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Edit: I note you match dotted-quad IP addresses frequently. If it helps, you can throw that pattern in a variable for re-use:

    my $IP_ADDR = qr/\d+\.\d+\.\d+\.\d+/;
    /...(?<src>$IP_ADDR).../

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In reply to Re: A better way to parse this with regexes? Pix ASA logs by rjt
in thread A better way to parse this with regexes? Pix ASA logs by symgryph

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