This bug was fixed in the package spamassassin - 3.4.1-7ubuntu1
--------------- spamassassin (3.4.1-7ubuntu1) artful; urgency=medium
* Apply upstream patch to fix regex error leading to warnings in perl 5.26+ (Closes: 869408) (LP: #1726879)
-- Christian Ehrhardt <email address hidden> Tue, 23 Jan 2018 17:00:08 +0100
This bug was fixed in the package spamassassin - 3.4.1-7ubuntu1
---------------
spamassassin (3.4.1-7ubuntu1) artful; urgency=medium
* Apply upstream patch to fix regex error leading to warnings in
perl 5.26+ (Closes: 869408) (LP: #1726879)
-- Christian Ehrhardt <email address hidden> Tue, 23 Jan 2018 17:00:08 +0100