crontab.c in crontab in FreeBSD and Apple Mac OS X allows local users to (1) determine the existence of arbitrary files via a symlink attack on a /tmp/crontab.XXXXXXXXXX temporary file and (2) perform MD5 checksum comparisons on arbitrary pairs of files via two symlink attacks on /tmp/crontab.XXXXXXXXXX temporary files.
marc.info/?l=full-disclosure&m=129891323028897&w=2
openwall.com/lists/oss-security/2011/02/28/14
openwall.com/lists/oss-security/2011/02/28/6
securityreason.com/securityalert/8117
www.securityfocus.com/archive/1/516716/100/0/threaded
www.securityfocus.com/bid/46604
exchange.xforce.ibmcloud.com/vulnerabilities/65899