`setuid` is a file permission flag under Unix-like systems that will run an executable with the file owner's permissions rather than the invoking user's. On some systems (FreeBSD), it further works identically to the related `setgid` flag on directories, causing new files to inherit the directory's permissions rather than the current user's.
Questions tagged [setuid]
254 questions
0
votes
1 answer
Why the set-uid operation can't be used in an excutable file?
When learning the system security in the ubuntu 20.04 on the VMware, I tried the set-uid operation and found the fllowing question:
With the excutable file catcall compiled by the source code…
dim_shimmer
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- 1
0
votes
0 answers
sh: 1: : not found when trying to open a new shell
I am trying to get a shell but it either doesn't open one or it throws an error and gets stuck saying
^[[B^[[B^[[B^[[B^[[B^[[B^[[B^[[B^[[B
sh: 1: : not found
Below is the .c code
#include
#include
#include
#include…
RRHS
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Problems with readlink and set uid
I'm having trouble getting setuid to work as hoped (chmod 3755).
I'm trying to implement, using C language, my own version of psgrep (or pgrep) for a very specific need. In order to accomplish this, I need to get the value of the link at…
Dennis
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1 answer
What is PARANOIA meaning on chroot and setuid?
I know paranoia meaning but I'm reading isc-dhcp source code and I got confused about this term in system programming and linux world.
configure.ac file has following codes :
# PARANOIA is off by default (until we can test it with all…
alirezaarzehgar
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0 answers
How can I using getrlimit to get normal user's nproc in c program
[root@api ~]# ulimit -u
3766
[zack@api ~]$ ulimit -u
5000
i cant fetch zack's nproc by using setuid(zackid) in program ,why?
[root@api dbhome]# ./a zack
UID:1000
EUID:1000
GID:1000
RLIMIT_NPROC cur:3766 // still root's nproc
zack
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0
votes
2 answers
setuid and setgid wotking with 0 (root) only, I want it to work other user
I'm trying to write a program that run /bin/bash with user smith privileges,
smith:x:1000:1000:Basket:/home/smith:/bin/bash
I tried this:
#include
#include
#include
int main () {
setgid(1000);
…
maksim lev
- 11
- 3
0
votes
1 answer
How to use setcap to enable setuid capability
I have the following c program.
$ cat main.c
#include
#include
#include
int main(int argc, char *argv[]) {
int fd;
if((fd = open(argv[1], O_RDONLY)) == -1) {
perror("open");
return 1;
}
…
user15482691
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- 1
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Linux setuid bit
As a normal user I can't seem to run the following bash script:
#/bin/bash
date 121001102020
The file permissions are: 4755
The file owner is: root
I would expect to be able to run this as a regular user. What I get is:
date: cannot set date:…
Blake McBride
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votes
1 answer
Create Linux user to access folder with rwxrwS--- (2760) permissions
I have a folder that has permissions set to 2760. The folder seems to be owned by www-data user and group.
drwxrwS--- 2 www-data www-data 196 Dec 5 19:52 folder
I added new user to www-data group, but it still cant access the folder without…
Kalvin Klien
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0
votes
1 answer
Why does SETUID not work on Raspberry Pi?
I am trying to create a shutdown command that can be run as a user, i.c., a flask web page that is not running as root. Sounds simple, just put a shutdown command in a SETUID script. Because SETUID does not work on shell scripts, I created an…
Roland
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2 answers
setuid: operation not supported
package main
import (
"log"
"syscall"
)
func main() {
setuidErr := syscall.Setuid(0)
if setuidErr != nil {
log.Fatal(setuidErr)
}
}
When I run above code, I get the following…
Ren
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votes
1 answer
Is it a sensible strategy to call setuid twice to clear the saved set-user ID?
For a program I'm developing, there's no reason why it should ever be run with setuid bit set - that always represents a configuration error on the part of the user. As part of defense in depth, I'd like to detect and fix that in the program.
As I…
Arthur Tacca
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1 answer
Setuid for iphone app to run as root
Im am trying to make my iphone app run as root, and i was told to setuid, I do not know how to do this.
Heli0s
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3 answers
Using setuid in Ubuntu to exec Java from C
I am running Ubuntu 11.04.
I am trying to use a "C" execlp program to run a Java program, and then I want to setuid on the "C" program so the Java program can execute as root. There is an example of this…
Herb Miller
- 31
- 3
0
votes
1 answer
Security Concerns on SetUID for non-privileged, malicious process (Linux)
I understand that setUID bit works with the EUID and RUID in Linux to give non-provisioned users temporary root access to executables that require it. However, my main concern is that let's say a process is malicious on a computer. Even if the…
Justin Tjoa
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