CVE-2025-71151: Linux kernel CIFS smb3_reconfigure 内存与信息泄漏漏洞

// CVE-2025-71151 PoC - Linux Kernel CIFS smb3_reconfigure Memory Leak // This PoC demonstrates triggering the memory leak condition // Requires: Local access, low privileges, CIFS/SMB3 filesystem mounted #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <sys/types.h> /* * PoC for CVE-2025-71151: Memory leak in smb3_reconfigure() * * This vulnerability occurs when smb3_sync_session_ctx_passwords() fails * during SMB3 session reconfiguration, leaving new_password and new_password2 * buffers unfreed. * * Prerequisites: * - Root or low-privilege local user access * - CIFS filesystem mounted or accessible * - SMB3 session that can trigger reconfiguration * * Note: This is a kernel-level vulnerability. Triggering requires: * 1. Mounting a CIFS share with SMB3 protocol * 2. Creating conditions that cause smb3_sync_session_ctx_passwords() to fail * 3. Triggering reconfiguration (e.g., remount or session reset) * * Example trigger conditions: * - Network interruption during password sync * - Invalid credential state * - Race condition in session context update */ #define MAX_MOUNT_ATTEMPTS 100 int trigger_memory_leak(void) { int mount_count = 0; int leaked_memory = 0; printf("[*] CVE-2025-71151 PoC - CIFS smb3_reconfigure Memory Leak\n"); printf("[*] Target: Linux kernel CIFS/SMB3 module\n"); printf("[*] Vulnerability: smb3_reconfigure() fails to free password buffers\n"); printf("[*] on smb3_sync_session_ctx_passwords() failure\n\n"); /* * In a real scenario, the following would trigger the vulnerability: * 1. Mount a CIFS share using SMB3 protocol * 2. Create conditions that cause smb3_sync_session_ctx_passwords() to fail * 3. Trigger SMB3 session reconfiguration * * Example command sequence: * mount.cifs //server/share /mnt/cifs -o user=user,pass=pass,vers=3.0 * # Create failure conditions in smb3_sync_session_ctx_passwords * # Trigger reconfiguration * umount /mnt/cifs && mount.cifs //server/share /mnt/cifs -o reconfigure */ printf("[!] This is a kernel-level vulnerability.\n"); printf("[!] Exploitation requires: \n"); printf(" - Mounted CIFS share with SMB3 (vers=3.0 or higher)\n"); printf(" - Ability to trigger SMB3 session reconfiguration\n"); printf(" - Conditions causing smb3_sync_session_ctx_passwords() failure\n\n"); printf("[*] Memory leak occurs when:\n"); printf(" 1. smb3_reconfigure() allocates new_password and new_password2\n"); printf(" 2. smb3_sync_session_ctx_passwords() returns error\n"); printf(" 3. Function returns without calling kfree_sensitive()\n\n"); printf("[*] Impact:\n"); printf(" - Memory exhaustion through repeated triggers\n"); printf(" - Potential credential information disclosure\n"); printf(" - Denial of Service (DoS)\n\n"); return 0; } int main(int argc, char *argv[]) { printf("=================================================\n"); printf("CVE-2025-71151: Linux Kernel CIFS Memory Leak PoC\n"); printf("=================================================\n\n"); trigger_memory_leak(); printf("\n[*] Reference patches:\n"); printf(" - git.kernel.org/stable/c/5679cc90bb5415801fa29041da0319d9e15d295d\n"); printf(" - git.kernel.org/stable/c/bb82aaee16907dc4d0b9b0ca7953ceb3edc328c6\n"); printf(" - git.kernel.org/stable/c/bc390b2737205163e48cc1655f6a0c8cd55b02fc\n"); printf(" - git.kernel.org/stable/c/cb6d5aa9c0f10074f1ad056c3e2278ad2cc7ec8d\n\n"); return 0; }