Lines Matching +full:enable +full:- +full:remote +full:- +full:sense

47 multi-user systems have some inherent security, the job of building and
60 As yesterday's mini-computers and mainframes
74 .Bl -enum -offset indent
89 Typically, DoS attacks are brute-force mechanisms that attempt
99 Brute-force network attacks are harder to deal with.
100 A spoofed-packet attack, for example, is
114 The result is that if you have any moderate-sized user base,
115 one or more of your users logging into your system from a remote location
119 his remote access logs looking for suspicious source addresses
137 may find a bug in a root-run server and be able to break root over a network
138 connection to that server, or the attacker may know of a bug in an SUID-root
152 Security remedies should always be implemented with a multi-layered
155 .Bl -enum -offset indent
159 Securing root \(em root-run servers and SUID/SGID binaries
279 .Xr ssh-keygen 1 .
281 to star-out the passwords for staff accounts also guarantees that staff
295 at all, and you should run a password-protected screen blanker.
299 consider the fact that the vast majority of break-ins occur remotely, over
311 re-passwording restrictions with Kerberos: not only can a Kerberos ticket
315 .Sh SECURING ROOT \(em ROOT-RUN SERVERS AND SUID/SGID BINARIES
317 Be aware that third party servers are often the most bug-prone.
374 servers as root and rely on other mechanisms to detect break-ins that might
377 The other big potential root hole in a system are the SUID-root and SGID
386 the system-default SUID and SGID binaries can be considered reasonably safe.
402 If an intruder can break an SGID-kmem binary the
418 program or emulator with a keyboard-simulation feature, the intruder can
425 draconian access restrictions on your staff and *-out their passwords, you
437 The only sure fire way is to *-out as many passwords as you can and
444 attacker cannot obtain root-write access.
515 read-only.
517 what you attempt to protect may prevent the all-important detection of an
521 Any super-user process can raise the level, but no process
524 .Bl -tag -width flag
525 .It Ic -1
526 Permanently insecure mode \- always run the system in insecure mode.
529 Insecure mode \- immutable and append-only flags may be turned off.
532 Secure mode \- the system immutable and system append-only flags may not
555 Highly secure mode \- same as secure mode, plus disks may not be
562 while the system is multi-user.
569 Network secure mode \- same as highly secure mode, plus
601 a false sense of safety) if you cannot detect potential incursions.
611 limited-access system.
612 Writing your security scripts on the extra-secure limited-access system
615 limited-access box significant access to the other machines in the business,
616 usually either by doing a read-only NFS export of the other machines to the
617 limited-access box, or by setting up SSH keypairs to allow the limit-access
623 limited-access server is connected to the client boxes through a switch,
625 If your limited-access server
627 of routing, the NFS method may be too insecure (network-wise) and using SSH
628 may be the better choice even with the audit-trail tracks that SSH lays.
630 Once you give a limit-access box at least read access to the client systems
640 the client-box files boxes at least once a
647 information the limited-access machine knows is valid, it should scream at
690 week, since the object of this layer is to detect a break-in whether or
691 not the break-in is effective.
696 is a relatively low-overhead feature of
697 the operating system which I recommend using as a post-break-in evaluation
701 the break-in occurs.
704 should be generated in as secure a manner as possible \(em remote syslog can be
708 break-in.
728 .Bl -enum -offset indent
755 Note that spoofed-IP attacks will circumvent
761 Some standalone servers have self-fork-limitation parameters.
788 separate from the queue-runs
790 If you still want real-time delivery you can run the queue
809 with connect-back services such as tcpwrapper's reverse-identd, which can
811 You generally do not want to use the reverse-ident
818 services from network-based root compromise.
824 ports A, B, C, D, and M-Z
831 and other internet-accessible services.
839 high-numbered port range on the firewall to allow permissive-like operation
854 internet-accessible ports, of course).
903 .Xr inetd 8 Ns -internal
944 key-forwarding in the SSH configuration, or that you make use of the
955 briefly listed there, together with controls which enable some mitigations
960 with backwards-compatibility shims to accept the existing names.
961 A future change will rationalize the sense of the individual sysctls
968 .Bl -tag -width security.bsd.unprivileged_proc_debug
981 sub-jails.
991 Controls availability of the process debugging facilities to non-root users.
997 Tunable, amd64-only.
999 tables are sanitized to prevent so-called Meltdown information leak on
1010 cross-process ret2spec attacks.
1027 Controls force-flush of L1D cache on return from syscalls which report
1042 Controls force-flush of L1D cache on NMI;
1055 .It Dv machdep.mitigations.rngds.enable
1061 and do not serialize off-core memory accesses.
1062 .It Dv kern.elf32.aslr.enable
1063 Controls system-global Address Space Layout Randomization (ASLR) for
1064 normal non-PIE (Position Independent Executable) 32-bit ELF binaries.
1068 mode, also affected by the per-image control note flag.
1070 Controls system-global Address Space Layout Randomization for
1071 position-independent (PIE) 32-bit binaries.
1076 Enable randomization of the stack for 32-bit binaries.
1079 .It Dv kern.elf64.aslr.enable
1080 ASLR control for 64-bit ELF binaries.
1082 ASLR control for 64-bit ELF PIEs.
1084 ASLR sbrk compatibility control for 64-bit binaries.
1086 Controls stack address randomization for 64-bit binaries.
1088 Enables non-executable stack for 32-bit processes.
1091 Enables non-executable stack for 64-bit processes.
1094 32-bit processes.
1097 64-bit processes.
1108 .Xr xdm 1 Pq Pa ports/x11/xorg-clients ,