/etc/logcheck/ignore.d.server/pureftp is in logcheck-database 1.3.14.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | ^\w{3} [ :0-9]{11} [._[:alnum:]-]+ pure-ftpd: \([._[:alnum:]-]+@[._[:alnum:]-]+\) \[ERROR\] Can't open .+: No such file or directory$
^\w{3} [ :0-9]{11} [._[:alnum:]-]+ pure-ftpd: \([._[:alnum:]-]+@[._[:alnum:]-]+\) \[ERROR\] Can't remove directory: No such file or directory$
^\w{3} [ :0-9]{11} [._[:alnum:]-]+ pure-ftpd: \(\?@[._[:alnum:]-]+\) \[DEBUG\] This is a private system - No anonymous login$
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