1SUDO(8) BSD System Manager's Manual SUDO(8)
2
4 sudo, sudoedit — execute a command as another user
5
7 sudo -h | -K | -k | -V
8 sudo -v [-ABknS] [-g group] [-h host] [-p prompt] [-u user]
9 sudo -l [-ABknS] [-g group] [-h host] [-p prompt] [-U user] [-u user]
10 [command]
11 sudo [-ABbEHnPS] [-C num] [-g group] [-h host] [-p prompt] [-r role]
12 [-t type] [-T timeout] [-u user] [VAR=value] [-i | -s] [command]
13 sudoedit [-ABknS] [-C num] [-g group] [-h host] [-p prompt] [-T timeout]
14 [-u user] file ...
15
17 sudo allows a permitted user to execute a command as the superuser or
18 another user, as specified by the security policy. The invoking user's
19 real (not effective) user-ID is used to determine the user name with
20 which to query the security policy.
21 sudo supports a plugin architecture for security policies and input/out‐
23 put logging. Third parties can develop and distribute their own policy
24 and I/O logging plugins to work seamlessly with the sudo front end. The
25 default security policy is sudoers, which is configured via the file
26 /etc/sudoers, or via LDAP. See the Plugins section for more information.
27 The security policy determines what privileges, if any, a user has to run
29 sudo. The policy may require that users authenticate themselves with a
30 password or another authentication mechanism. If authentication is
31 required, sudo will exit if the user's password is not entered within a
32 configurable time limit. This limit is policy-specific; the default
33 password prompt timeout for the sudoers security policy is 5 minutes.
34 Security policies may support credential caching to allow the user to run
36 sudo again for a period of time without requiring authentication. By
37 default, the sudoers policy caches credentials on a per-terminal basis
38 for 5 minutes. See the timestamp_type and timestamp_timeout options in
39 sudoers(5) for more information. By running sudo with the -v option, a
40 user can update the cached credentials without running a command.
41 When invoked as sudoedit, the -e option (described below), is implied.
43 Security policies may log successful and failed attempts to use sudo. If
45 an I/O plugin is configured, the running command's input and output may
46 be logged as well.
47 The options are as follows:
49 -A, --askpass
51 Normally, if sudo requires a password, it will read it from
52 the user's terminal. If the -A (askpass) option is speci‐
53 fied, a (possibly graphical) helper program is executed to
54 read the user's password and output the password to the stan‐
55 dard output. If the SUDO_ASKPASS environment variable is
56 set, it specifies the path to the helper program. Otherwise,
57 if sudo.conf(5) contains a line specifying the askpass pro‐
58 gram, that value will be used. For example:
59 # Path to askpass helper program
61 Path askpass /usr/X11R6/bin/ssh-askpass
62 If no askpass program is available, sudo will exit with an
64 error.
65 -B, --bell Ring the bell as part of the password promp when a terminal
67 is present. This option has no effect if an askpass program
68 is used.
69 -b, --background
71 Run the given command in the background. Note that it is not
72 possible to use shell job control to manipulate background
73 processes started by sudo. Most interactive commands will
74 fail to work properly in background mode.
75 -C num, --close-from=num
77 Close all file descriptors greater than or equal to num
78 before executing a command. Values less than three are not
79 permitted. By default, sudo will close all open file
80 descriptors other than standard input, standard output and
81 standard error when executing a command. The security policy
82 may restrict the user's ability to use this option. The
83 sudoers policy only permits use of the -C option when the
84 administrator has enabled the closefrom_override option.
85 -E, --preserve-env
87 Indicates to the security policy that the user wishes to pre‐
88 serve their existing environment variables. The security
89 policy may return an error if the user does not have permis‐
90 sion to preserve the environment.
91 --preserve-env=list
93 Indicates to the security policy that the user wishes to add
94 the comma-separated list of environment variables to those
95 preserved from the user's environment. The security policy
96 may return an error if the user does not have permission to
97 preserve the environment.
98 -e, --edit Edit one or more files instead of running a command. In lieu
100 of a path name, the string "sudoedit" is used when consulting
101 the security policy. If the user is authorized by the pol‐
102 icy, the following steps are taken:
103 1. Temporary copies are made of the files to be edited with
105 the owner set to the invoking user.
106 2. The editor specified by the policy is run to edit the
108 temporary files. The sudoers policy uses the
109 SUDO_EDITOR, VISUAL and EDITOR environment variables (in
110 that order). If none of SUDO_EDITOR, VISUAL or EDITOR
111 are set, the first program listed in the editor
112 sudoers(5) option is used.
113 3. If they have been modified, the temporary files are
115 copied back to their original location and the temporary
116 versions are removed.
117 To help prevent the editing of unauthorized files, the fol‐
119 lowing restrictions are enforced unless explicitly allowed by
120 the security policy:
121 · Symbolic links may not be edited (version 1.8.15 and
123 higher).
124 · Symbolic links along the path to be edited are not fol‐
126 lowed when the parent directory is writable by the invok‐
127 ing user unless that user is root (version 1.8.16 and
128 higher).
129 · Files located in a directory that is writable by the
131 invoking user may not be edited unless that user is root
132 (version 1.8.16 and higher).
133 Users are never allowed to edit device special files.
135 If the specified file does not exist, it will be created.
137 Note that unlike most commands run by sudo, the editor is run
138 with the invoking user's environment unmodified. If, for
139 some reason, sudo is unable to update a file with its edited
140 version, the user will receive a warning and the edited copy
141 will remain in a temporary file.
142 -g group, --group=group
144 Run the command with the primary group set to group instead
145 of the primary group specified by the target user's password
146 database entry. The group may be either a group name or a
147 numeric group-ID (GID) prefixed with the ‘#’ character (e.g.,
148 #0 for GID 0). When running a command as a GID, many shells
149 require that the ‘#’ be escaped with a backslash (‘\’). If
150 no -u option is specified, the command will be run as the
151 invoking user. In either case, the primary group will be set
152 to group. The sudoers policy permits any of the target
153 user's groups to be specified via the -g option as long as
154 the -P option is not in use.
155 -H, --set-home
157 Request that the security policy set the HOME environment
158 variable to the home directory specified by the target user's
159 password database entry. Depending on the policy, this may
160 be the default behavior.
161 -h, --help Display a short help message to the standard output and exit.
163 -h host, --host=host
165 Run the command on the specified host if the security policy
166 plugin supports remote commands. Note that the sudoers plug‐
167 in does not currently support running remote commands. This
168 may also be used in conjunction with the -l option to list a
169 user's privileges for the remote host.
170 -i, --login
172 Run the shell specified by the target user's password data‐
173 base entry as a login shell. This means that login-specific
174 resource files such as .profile, .bash_profile or .login will
175 be read by the shell. If a command is specified, it is
176 passed to the shell for execution via the shell's -c option.
177 If no command is specified, an interactive shell is executed.
178 sudo attempts to change to that user's home directory before
179 running the shell. The command is run with an environment
180 similar to the one a user would receive at log in. Note that
181 most shells behave differently when a command is specified as
182 compared to an interactive session; consult the shell's man‐
183 ual for details. The Command environment section in the
184 sudoers(5) manual documents how the -i option affects the
185 environment in which a command is run when the sudoers policy
186 is in use.
187 -K, --remove-timestamp
189 Similar to the -k option, except that it removes the user's
190 cached credentials entirely and may not be used in conjunc‐
191 tion with a command or other option. This option does not
192 require a password. Not all security policies support cre‐
193 dential caching.
194 -k, --reset-timestamp
196 When used without a command, invalidates the user's cached
197 credentials. In other words, the next time sudo is run a
198 password will be required. This option does not require a
199 password and was added to allow a user to revoke sudo permis‐
200 sions from a .logout file.
201 When used in conjunction with a command or an option that may
203 require a password, this option will cause sudo to ignore the
204 user's cached credentials. As a result, sudo will prompt for
205 a password (if one is required by the security policy) and
206 will not update the user's cached credentials.
207 Not all security policies support credential caching.
209 -l, --list If no command is specified, list the allowed (and forbidden)
211 commands for the invoking user (or the user specified by the
212 -U option) on the current host. A longer list format is used
213 if this option is specified multiple times and the security
214 policy supports a verbose output format.
215 If a command is specified and is permitted by the security
217 policy, the fully-qualified path to the command is displayed
218 along with any command line arguments. If a command is spec‐
219 ified but not allowed by the policy, sudo will exit with a
220 status value of 1.
221 -n, --non-interactive
223 Avoid prompting the user for input of any kind. If a pass‐
224 word is required for the command to run, sudo will display an
225 error message and exit.
226 -P, --preserve-groups
228 Preserve the invoking user's group vector unaltered. By
229 default, the sudoers policy will initialize the group vector
230 to the list of groups the target user is a member of. The
231 real and effective group-IDs, however, are still set to match
232 the target user.
233 -p prompt, --prompt=prompt
235 Use a custom password prompt with optional escape sequences.
236 The following percent (‘%’) escape sequences are supported by
237 the sudoers policy:
238 %H expanded to the host name including the domain name (on
240 if the machine's host name is fully qualified or the fqdn
241 option is set in sudoers(5))
242 %h expanded to the local host name without the domain name
244 %p expanded to the name of the user whose password is being
246 requested (respects the rootpw, targetpw, and runaspw
247 flags in sudoers(5))
248 %U expanded to the login name of the user the command will
250 be run as (defaults to root unless the -u option is also
251 specified)
252 %u expanded to the invoking user's login name
254 %% two consecutive ‘%’ characters are collapsed into a sin‐
256 gle ‘%’ character
257 The custom prompt will override the default prompt specified
259 by either the security policy or the SUDO_PROMPT environment
260 variable. On systems that use PAM, the custom prompt will
261 also override the prompt specified by a PAM module unless the
262 passprompt_override flag is disabled in sudoers.
263 -r role, --role=role
265 Run the command with an SELinux security context that
266 includes the specified role.
267 -S, --stdin
269 Write the prompt to the standard error and read the password
270 from the standard input instead of using the terminal device.
271 -s, --shell
273 Run the shell specified by the SHELL environment variable if
274 it is set or the shell specified by the invoking user's pass‐
275 word database entry. If a command is specified, it is passed
276 to the shell for execution via the shell's -c option. If no
277 command is specified, an interactive shell is executed. Note
278 that most shells behave differently when a command is speci‐
279 fied as compared to an interactive session; consult the
280 shell's manual for details.
281 -t type, --type=type
283 Run the command with an SELinux security context that
284 includes the specified type. If no type is specified, the
285 default type is derived from the role.
286 -U user, --other-user=user
288 Used in conjunction with the -l option to list the privileges
289 for user instead of for the invoking user. The security pol‐
290 icy may restrict listing other users' privileges. The
291 sudoers policy only allows root or a user with the ALL privi‐
292 lege on the current host to use this option.
293 -T timeout, --command-timeout=timeout
295 Used to set a timeout for the command. If the timeout
296 expires before the command has exited, the command will be
297 terminated. The security policy may restrict the ability to
298 set command timeouts. The sudoers policy requires that user-
299 specified timeouts be explicitly enabled.
300 -u user, --user=user
302 Run the command as a user other than the default target user
303 (usually root). The user may be either a user name or a
304 numeric user-ID (UID) prefixed with the ‘#’ character (e.g.,
305 #0 for UID 0). When running commands as a UID, many shells
306 require that the ‘#’ be escaped with a backslash (‘\’). Some
307 security policies may restrict UIDs to those listed in the
308 password database. The sudoers policy allows UIDs that are
309 not in the password database as long as the targetpw option
310 is not set. Other security policies may not support this.
311 -V, --version
313 Print the sudo version string as well as the version string
314 of the security policy plugin and any I/O plugins. If the
315 invoking user is already root the -V option will display the
316 arguments passed to configure when sudo was built and plugins
317 may display more verbose information such as default options.
318 -v, --validate
320 Update the user's cached credentials, authenticating the user
321 if necessary. For the sudoers plugin, this extends the sudo
322 timeout for another 5 minutes by default, but does not run a
323 command. Not all security policies support cached creden‐
324 tials.
325 -- The -- option indicates that sudo should stop processing com‐
327 mand line arguments.
328 Environment variables to be set for the command may also be passed on the
330 command line in the form of VAR=value, e.g.,
331 LD_LIBRARY_PATH=/usr/local/pkg/lib. Variables passed on the command line
332 are subject to restrictions imposed by the security policy plugin. The
333 sudoers policy subjects variables passed on the command line to the same
334 restrictions as normal environment variables with one important excep‐
335 tion. If the setenv option is set in sudoers, the command to be run has
336 the SETENV tag set or the command matched is ALL, the user may set vari‐
337 ables that would otherwise be forbidden. See sudoers(5) for more infor‐
338 mation.
339
341 When sudo executes a command, the security policy specifies the execution
342 environment for the command. Typically, the real and effective user and
343 group and IDs are set to match those of the target user, as specified in
344 the password database, and the group vector is initialized based on the
345 group database (unless the -P option was specified).
346 The following parameters may be specified by security policy:
348 · real and effective user-ID
350 · real and effective group-ID
352 · supplementary group-IDs
354 · the environment list
356 · current working directory
358 · file creation mode mask (umask)
360 · SELinux role and type
362 · scheduling priority (aka nice value)
364 Process model
366 There are two distinct ways sudo can run a command.
367 If an I/O logging plugin is configured or if the security policy explic‐
369 itly requests it, a new pseudo-terminal (“pty”) is allocated and fork(2)
370 is used to create a second sudo process, referred to as the monitor. The
371 monitor creates a new terminal session with itself as the leader and the
372 pty as its controlling terminal, calls fork(2), sets up the execution
373 environment as described above, and then uses the execve(2) system call
374 to run the command in the child process. The monitor exists to relay job
375 control signals between the user's existing terminal and the pty the com‐
376 mand is being run in. This makes it possible to suspend and resume the
377 command. Without the monitor, the command would be in what POSIX terms
378 an “orphaned process group” and it would not receive any job control sig‐
379 nals from the kernel. When the command exits or is terminated by a sig‐
380 nal, the monitor passes the command's exit status to the main sudo
381 process and exits. After receiving the command's exit status, the main
382 sudo passes the command's exit status to the security policy's close
383 function and exits.
384 If no pty is used, sudo calls fork(2), sets up the execution environment
386 as described above, and uses the execve(2) system call to run the command
387 in the child process. The main sudo process waits until the command has
388 completed, then passes the command's exit status to the security policy's
389 close function and exits. As a special case, if the policy plugin does
390 not define a close function, sudo will execute the command directly
391 instead of calling fork(2) first. The sudoers policy plugin will only
392 define a close function when I/O logging is enabled, a pty is required,
393 or the pam_session or pam_setcred options are enabled. Note that
394 pam_session and pam_setcred are enabled by default on systems using PAM.
395 Signal handling
397 When the command is run as a child of the sudo process, sudo will relay
398 signals it receives to the command. The SIGINT and SIGQUIT signals are
399 only relayed when the command is being run in a new pty or when the sig‐
400 nal was sent by a user process, not the kernel. This prevents the com‐
401 mand from receiving SIGINT twice each time the user enters control-C.
402 Some signals, such as SIGSTOP and SIGKILL, cannot be caught and thus will
403 not be relayed to the command. As a general rule, SIGTSTP should be used
404 instead of SIGSTOP when you wish to suspend a command being run by sudo.
405 As a special case, sudo will not relay signals that were sent by the com‐
407 mand it is running. This prevents the command from accidentally killing
408 itself. On some systems, the reboot(8) command sends SIGTERM to all non-
409 system processes other than itself before rebooting the system. This
410 prevents sudo from relaying the SIGTERM signal it received back to
411 reboot(8), which might then exit before the system was actually rebooted,
412 leaving it in a half-dead state similar to single user mode. Note, how‐
413 ever, that this check only applies to the command run by sudo and not any
414 other processes that the command may create. As a result, running a
415 script that calls reboot(8) or shutdown(8) via sudo may cause the system
416 to end up in this undefined state unless the reboot(8) or shutdown(8) are
417 run using the exec() family of functions instead of system() (which
418 interposes a shell between the command and the calling process).
419 If no I/O logging plugins are loaded and the policy plugin has not
421 defined a close() function, set a command timeout or required that the
422 command be run in a new pty, sudo may execute the command directly
423 instead of running it as a child process.
424 Plugins
426 Plugins may be specified via Plugin directives in the sudo.conf(5) file.
427 They may be loaded as dynamic shared objects (on systems that support
428 them), or compiled directly into the sudo binary. If no sudo.conf(5)
429 file is present, or it contains no Plugin lines, sudo will use the tradi‐
430 tional sudoers security policy and I/O logging. See the sudo.conf(5)
431 manual for details of the /etc/sudo.conf file and the sudo_plugin(5) man‐
432 ual for more information about the sudo plugin architecture.
433
435 Upon successful execution of a command, the exit status from sudo will be
436 the exit status of the program that was executed. If the command termi‐
437 nated due to receipt of a signal, sudo will send itself the same signal
438 that terminated the command.
439 If the -l option was specified without a command, sudo will exit with a
441 value of 0 if the user is allowed to run sudo and they authenticated suc‐
442 cessfully (as required by the security policy). If a command is speci‐
443 fied with the -l option, the exit value will only be 0 if the command is
444 permitted by the security policy, otherwise it will be 1.
445 If there is an authentication failure, a configuration/permission problem
447 or if the given command cannot be executed, sudo exits with a value of 1.
448 In the latter case, the error string is printed to the standard error.
449 If sudo cannot stat(2) one or more entries in the user's PATH, an error
450 is printed to the standard error. (If the directory does not exist or if
451 it is not really a directory, the entry is ignored and no error is
452 printed.) This should not happen under normal circumstances. The most
453 common reason for stat(2) to return “permission denied” is if you are
454 running an automounter and one of the directories in your PATH is on a
455 machine that is currently unreachable.
456
458 sudo tries to be safe when executing external commands.
459 To prevent command spoofing, sudo checks "." and "" (both denoting cur‐
461 rent directory) last when searching for a command in the user's PATH (if
462 one or both are in the PATH). Note, however, that the actual PATH envi‐
463 ronment variable is not modified and is passed unchanged to the program
464 that sudo executes.
465 Users should never be granted sudo privileges to execute files that are
467 writable by the user or that reside in a directory that is writable by
468 the user. If the user can modify or replace the command there is no way
469 to limit what additional commands they can run.
470 Please note that sudo will normally only log the command it explicitly
472 runs. If a user runs a command such as sudo su or sudo sh, subsequent
473 commands run from that shell are not subject to sudo's security policy.
474 The same is true for commands that offer shell escapes (including most
475 editors). If I/O logging is enabled, subsequent commands will have their
476 input and/or output logged, but there will not be traditional logs for
477 those commands. Because of this, care must be taken when giving users
478 access to commands via sudo to verify that the command does not inadver‐
479 tently give the user an effective root shell. For more information,
480 please see the Preventing shell escapes section in sudoers(5).
481 To prevent the disclosure of potentially sensitive information, sudo dis‐
483 ables core dumps by default while it is executing (they are re-enabled
484 for the command that is run). This historical practice dates from a time
485 when most operating systems allowed set-user-ID processes to dump core by
486 default. To aid in debugging sudo crashes, you may wish to re-enable
487 core dumps by setting “disable_coredump” to false in the sudo.conf(5)
488 file as follows:
489 Set disable_coredump false
491 See the sudo.conf(5) manual for more information.
493
495 sudo utilizes the following environment variables. The security policy
496 has control over the actual content of the command's environment.
497 EDITOR Default editor to use in -e (sudoedit) mode if neither
499 SUDO_EDITOR nor VISUAL is set.
500 MAIL Set to the mail spool of the target user when the -i
502 option is specified or when env_reset is enabled in
503 sudoers (unless MAIL is present in the env_keep list).
504 HOME Set to the home directory of the target user when the -i
506 or -H options are specified, when the -s option is spec‐
507 ified and set_home is set in sudoers, when
508 always_set_home is enabled in sudoers, or when env_reset
509 is enabled in sudoers and HOME is not present in the
510 env_keep list.
511 LOGNAME Set to the login name of the target user when the -i
513 option is specified, when the set_logname option is
514 enabled in sudoers or when the env_reset option is
515 enabled in sudoers (unless LOGNAME is present in the
516 env_keep list).
517 PATH May be overridden by the security policy.
519 SHELL Used to determine shell to run with -s option.
521 SUDO_ASKPASS Specifies the path to a helper program used to read the
523 password if no terminal is available or if the -A option
524 is specified.
525 SUDO_COMMAND Set to the command run by sudo.
527 SUDO_EDITOR Default editor to use in -e (sudoedit) mode.
529 SUDO_GID Set to the group-ID of the user who invoked sudo.
531 SUDO_PROMPT Used as the default password prompt unless the -p option
533 was specified.
534 SUDO_PS1 If set, PS1 will be set to its value for the program
536 being run.
537 SUDO_UID Set to the user-ID of the user who invoked sudo.
539 SUDO_USER Set to the login name of the user who invoked sudo.
541 USER Set to the same value as LOGNAME, described above.
543 VISUAL Default editor to use in -e (sudoedit) mode if
545 SUDO_EDITOR is not set.
546
548 /etc/sudo.conf sudo front end configuration
549
551 Note: the following examples assume a properly configured security pol‐
552 icy.
553 To get a file listing of an unreadable directory:
555 $ sudo ls /usr/local/protected
557 To list the home directory of user yaz on a machine where the file system
559 holding ~yaz is not exported as root:
560 $ sudo -u yaz ls ~yaz
562 To edit the index.html file as user www:
564 $ sudoedit -u www ~www/htdocs/index.html
566 To view system logs only accessible to root and users in the adm group:
568 $ sudo -g adm more /var/log/syslog
570 To run an editor as jim with a different primary group:
572 $ sudoedit -u jim -g audio ~jim/sound.txt
574 To shut down a machine:
576 $ sudo shutdown -r +15 "quick reboot"
578 To make a usage listing of the directories in the /home partition. Note
580 that this runs the commands in a sub-shell to make the cd and file redi‐
581 rection work.
582 $ sudo sh -c "cd /home ; du -s * | sort -rn > USAGE"
584
586 Error messages produced by sudo include:
587 editing files in a writable directory is not permitted
589 By default, sudoedit does not permit editing a file when any of the
590 parent directories are writable by the invoking user. This avoids
591 a race condition that could allow the user to overwrite an arbi‐
592 trary file. See the sudoedit_checkdir option in sudoers(5) for
593 more information.
594 editing symbolic links is not permitted
596 By default, sudoedit does not follow symbolic links when opening
597 files. See the sudoedit_follow option in sudoers(5) for more
598 information.
599 effective uid is not 0, is sudo installed setuid root?
601 sudo was not run with root privileges. The sudo binary must be
602 owned by the root user and have the set-user-ID bit set. Also, it
603 must not be located on a file system mounted with the ‘nosuid’
604 option or on an NFS file system that maps uid 0 to an unprivileged
605 uid.
606 effective uid is not 0, is sudo on a file system with the 'nosuid' option
608 set or an NFS file system without root privileges?
609 sudo was not run with root privileges. The sudo binary has the
610 proper owner and permissions but it still did not run with root
611 privileges. The most common reason for this is that the file sys‐
612 tem the sudo binary is located on is mounted with the ‘nosuid’
613 option or it is an NFS file system that maps uid 0 to an unprivi‐
614 leged uid.
615 fatal error, unable to load plugins
617 An error occurred while loading or initializing the plugins speci‐
618 fied in sudo.conf(5).
619 invalid environment variable name
621 One or more environment variable names specified via the -E option
622 contained an equal sign (‘=’). The arguments to the -E option
623 should be environment variable names without an associated value.
624 no password was provided
626 When sudo tried to read the password, it did not receive any char‐
627 acters. This may happen if no terminal is available (or the -S
628 option is specified) and the standard input has been redirected
629 from /dev/null.
630 a terminal is required to read the password
632 sudo needs to read the password but there is no mechanism available
633 for it to do so. A terminal is not present to read the password
634 from, sudo has not been configured to read from the standard input,
635 the -S option was not used, and no askpass helper has been speci‐
636 fied either via the sudo.conf(5) file or the SUDO_ASKPASS environ‐
637 ment variable.
638 no writable temporary directory found
640 sudoedit was unable to find a usable temporary directory in which
641 to store its intermediate files.
642 sudo must be owned by uid 0 and have the setuid bit set
644 sudo was not run with root privileges. The sudo binary does not
645 have the correct owner or permissions. It must be owned by the
646 root user and have the set-user-ID bit set.
647 sudoedit is not supported on this platform
649 It is only possible to run sudoedit on systems that support setting
650 the effective user-ID.
651 timed out reading password
653 The user did not enter a password before the password timeout (5
654 minutes by default) expired.
655 you do not exist in the passwd database
657 Your user-ID does not appear in the system passwd database.
658 you may not specify environment variables in edit mode
660 It is only possible to specify environment variables when running a
661 command. When editing a file, the editor is run with the user's
662 environment unmodified.
663
665 su(1), stat(2), login_cap(3), passwd(5), sudo.conf(5), sudo_plugin(5),
666 sudoers(5), sudoers_timestamp(5), sudoreplay(8), visudo(8)
667
669 See the HISTORY file in the sudo distribution (https://www.sudo.ws/his‐
670 tory.html) for a brief history of sudo.
671
673 Many people have worked on sudo over the years; this version consists of
674 code written primarily by:
675 Todd C. Miller
677 See the CONTRIBUTORS file in the sudo distribution
679 (https://www.sudo.ws/contributors.html) for an exhaustive list of people
680 who have contributed to sudo.
681
683 There is no easy way to prevent a user from gaining a root shell if that
684 user is allowed to run arbitrary commands via sudo. Also, many programs
685 (such as editors) allow the user to run commands via shell escapes, thus
686 avoiding sudo's checks. However, on most systems it is possible to pre‐
687 vent shell escapes with the sudoers(5) plugin's noexec functionality.
688 It is not meaningful to run the cd command directly via sudo, e.g.,
690 $ sudo cd /usr/local/protected
692 since when the command exits the parent process (your shell) will still
694 be the same. Please see the EXAMPLES section for more information.
695 Running shell scripts via sudo can expose the same kernel bugs that make
697 set-user-ID shell scripts unsafe on some operating systems (if your OS
698 has a /dev/fd/ directory, set-user-ID shell scripts are generally safe).
699
701 If you feel you have found a bug in sudo, please submit a bug report at
702 https://bugzilla.sudo.ws/
703
705 Limited free support is available via the sudo-users mailing list, see
706 https://www.sudo.ws/mailman/listinfo/sudo-users to subscribe or search
707 the archives.
708
710 sudo is provided “AS IS” and any express or implied warranties, includ‐
711 ing, but not limited to, the implied warranties of merchantability and
712 fitness for a particular purpose are disclaimed. See the LICENSE file
713 distributed with sudo or https://www.sudo.ws/license.html for complete
714 details.
715Sudo 1.9.0b4 October 20, 2019 Sudo 1.9.0b4