Everything Sysadmin

Today's Unix Security Trivia

If you write to a file that is SUID (or SGID) the SUID (and SGID) bits on the file are removed as a security precaution against tampering (unless uid 0 is doing the writing).

(See FreeBSD 5.4 source code, sys/ufs/ffs/ffs_vnops.c:739)