🔍 CVE-2024-50033

9.8
CVSS Score
CRITICAL
2024-10-21
2026-10-15 01:19
✅ 완료

🇰🇷 한글 설명

Linux 커널의 slip 드라이버 내 slhc_remember() 함수에서 악성 패킷에 대한 검증이 미흡하여 발생하는 취약점입니다. 패킷 크기만 확인하고 IPv4 및 TCP 헤더의 유효성을 충분히 검사하지 않아 초기화되지 않은 메모리 값을 참조할 수 있는 KMSAN 오류가 발생합니다.

💡 쉬운 설명

네트워크 패킷을 처리할 때 데이터가 올바른 형식인지 제대로 확인하지 않아 발생하는 보안 결함입니다. 공격자가 조작된 패킷을 보내 시스템의 메모리 오류를 유발하거나 비정상적인 동작을 일으킬 수 있습니다.

🇺🇸 원문 (English)

In the Linux kernel, the following vulnerability has been resolved: slip: make slhc_remember() more robust against malicious packets syzbot found that slhc_remember() was missing checks against malicious packets [1]. slhc_remember() only checked the size of the packet was at least 20, which is not good enough. We need to make sure the packet includes the IPv4 and TCP header that are supposed to be carried. Add iph and th pointers to make the code more readable. [1] BUG: KMSAN: uninit-value in slhc_remember+0x2e8/0x7b0 drivers/net/slip/slhc.c:666 slhc_remember+0x2e8/0x7b0 drivers/net/slip/slhc.c:666 ppp_receive_nonmp_frame+0xe45/0x35e0 drivers/net/ppp/ppp_generic.c:2455 ppp_receive_frame drivers/net/ppp/ppp_generic.c:2372 [inline] ppp_do_recv+0x65f/0x40d0 drivers/net/ppp/ppp_generic.c:2212 ppp_input+0x7dc/0xe60 drivers/net/ppp/ppp_generic.c:2327 pppoe_rcv_core+0x1d3/0x720 drivers/net/ppp/pppoe.c:379 sk_backlog_rcv+0x13b/0x420 include/net/sock.h:1113 __release_sock+0x1da/0x330 net/core/sock.c:3072 release_sock+0x6b/0x250 net/core/sock.c:3626 pppoe_sendmsg+0x2b8/0xb90 drivers/net/ppp/pppoe.c:903 sock_sendmsg_nosec net/socket.c:729 [inline] __sock_sendmsg+0x30f/0x380 net/socket.c:744 ____sys_sendmsg+0x903/0xb60 net/socket.c:2602 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2656 __sys_sendmmsg+0x3c1/0x960 net/socket.c:2742 __do_sys_sendmmsg net/socket.c:2771 [inline] __se_sys_sendmmsg net/socket.c:2768 [inline] __x64_sys_sendmmsg+0xbc/0x120 net/socket.c:2768 x64_sys_call+0xb6e/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:308 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Uninit was created at: slab_post_alloc_hook mm/slub.c:4091 [inline] slab_alloc_node mm/slub.c:4134 [inline] kmem_cache_alloc_node_noprof+0x6bf/0xb80 mm/slub.c:4186 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:587 __alloc_skb+0x363/0x7b0 net/core/skbuff.c:678 alloc_skb include/linux/skbuff.h:1322 [inline] sock_wmalloc+0xfe/0x1a0 net/core/sock.c:2732 pppoe_sendmsg+0x3a7/0xb90 drivers/net/ppp/pppoe.c:867 sock_sendmsg_nosec net/socket.c:729 [inline] __sock_sendmsg+0x30f/0x380 net/socket.c:744 ____sys_sendmsg+0x903/0xb60 net/socket.c:2602 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2656 __sys_sendmmsg+0x3c1/0x960 net/socket.c:2742 __do_sys_sendmmsg net/socket.c:2771 [inline] __se_sys_sendmmsg net/socket.c:2768 [inline] __x64_sys_sendmmsg+0xbc/0x120 net/socket.c:2768 x64_sys_call+0xb6e/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:308 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f CPU: 0 UID: 0 PID: 5460 Comm: syz.2.33 Not tainted 6.12.0-rc2-syzkaller-00006-g87d6aab2389e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024

📍 영향받는 시스템

Linux kernel (specifically versions using slip/slhc.c, including 6.12.0-rc2 and earlier)

⚔️ 공격 벡터

조작된 IPv4/TCP 헤더를 포함한 악성 네트워크 패킷을 전송하여 커널의 slhc_remember() 함수를 호출

🛡️ 대응 방법

Linux 커널을 최신 보안 패치가 적용된 버전으로 업데이트하여 slhc_remember()의 패킷 검증 로직을 강화해야 합니다.

🔧 검증 코드

출력된 커널 버전이 취약점이 해결된 패치 버전 이후인지 확인합니다.

Shell / Script
uname -r

📊 CVSS Vector String

CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

💻 영향받는 소프트웨어

Linux Kernel