xref: /openbsd-src/share/man/man8/security.8 (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e)
1.\" $OpenBSD: security.8,v 1.3 2001/06/27 21:19:22 pvalchev Exp $
2.Dd July 1, 2000
3.Dt SECURITY 8
4.Os
5.Sh NAME
6.Nm security
7.Nd periodic system security check
8.Sh SYNOPSIS
9.Nm /etc/security
10.Sh DESCRIPTION
11.Nm
12is a command script that examines the system for some signs of security
13weaknesses.
14It is only a security aid and does not offer complete protection.
15The
16.Nm
17script is normally run from the
18.Pa /etc/daily
19script, which sends mails to root on a daily basis.
20.Pp
21The
22.Nm
23script carries out the following list of simple checks:
24.Bl -bullet
25.It
26Check the master
27.Xr passwd 5
28and
29.Xr group 5
30files for
31syntax, empty passwords, partially closed accounts,
32suspicious UIDs, suspicious GIDs, and duplicate entries.
33.It
34Check root's home directory and login environment for
35insecure permissions, suspicious paths, and umask commands in the
36dotfiles.
37.It
38Check that root and uucp are in
39.Pa /etc/ftpusers .
40.It
41Check for suspicious commands in
42.Pa /etc/mail/aliases .
43.It
44Check for insecurities in various trust files such as
45.Pa /etc/hosts.equiv , /etc/shosts.equiv ,
46and
47.Pa /etc/hosts.lpd .
48.It
49Check user
50.Pa .rhosts
51and
52.Pa .shosts
53files for open access.
54.It
55Check user home directory permissions.
56.It
57Check many user dotfile permissions.
58.It
59Check user mailbox permissions.
60.It
61Check NFS
62.Xr exports 5
63file for global export entries.
64.It
65Check for changes in setuid/setgid files and devices.
66.It
67Check disk ownership and permissions.
68.It
69Check for changes in the device file list.
70.It
71Check for permission changes in special files and system binaries listed in
72.Pa /etc/mtree/special
73and
74.Pa "/etc/mtree/*.secure" .
75.Sy Note:
76This is not complete protection against Trojan horsed binaries, as
77the miscreant can modify the tree specification to match the replaced binary.
78For details on really protecting yourself against modified binaries, see
79.Xr mtree 8 .
80.It
81Check for content changes in those files specified by
82.Pa /etc/changelist .
83.El
84.Pp
85The intent of the
86.Nm
87script is to point out some obvious holes to the system administrator.
88.Sh FILES
89.Bl -tag -width /dev/changelist -compact
90.It Pa /etc/daily
91.It Pa /etc/mtree
92.It Pa /etc/changelist
93.It Pa /var/backups
94.El
95.Sh SEE ALSO
96.Xr mtree 8
97.Sh BUGS
98The name of this script may provide a false sense of
99.Nm security .
100.\" Well, I thought it was amusing.
101.Pp
102There are perhaps an infinite number of ways the system can be compromised
103without this script noticing.
104