inmail-show in mh-book 200605 allows local users to overwrite arbitrary files via a symlink attack on a (1) /tmp/inmail#####.log or (2) /tmp/inmail#####.stdin temporary file.
https://exchange.xforce.ibmcloud.com/vulnerabilities/46709
https://euvd.enisa.europa.eu/vulnerability/EUVD-2008-5131