Linux Distros 未修補弱點：CVE-2024-36933
medium Nessus Plugin ID 228396
語言:
概要
Linux/Unix 主機上安裝的一個或多個套件存有弱點，供應商表示將不會修補。說明
Linux/Unix 主機上安裝了一個或多個受到弱點影響的套件，且供應商未提供可用的修補程式。- 在 Linux 核心中，已解決下列弱點： nsh: Restore skb->{protocol,data,mac_header} for outer header in nsh_gso_segment(). syzbot triggered various splats (see [0] and links) by a crafted GSO packet of VIRTIO_NET_HDR_GSO_UDP layering the following protocols:
ETH_P_8021AD + ETH_P_NSH + ETH_P_IPV6 + IPPROTO_UDP NSH can encapsulate IPv4, IPv6, Ethernet, NSH, and MPLS. As the inner protocol can be Ethernet, NSH GSO handler, nsh_gso_segment(), calls skb_mac_gso_segment() to invoke inner protocol GSO handlers. nsh_gso_segment() does the following for the original skb before calling skb_mac_gso_segment() 1. reset skb->network_header 2. save the original skb->{mac_heaeder,mac_len} in a local variable 3. pull the NSH header 4. resets skb->mac_header 5. set up skb->mac_len and skb->protocol for the inner protocol. and does the following for the segmented skb 6. set ntohs(ETH_P_NSH) to skb->protocol 7. push the NSH header 8. restore skb->mac_header 9. set skb->mac_header + mac_len to skb->network_header 10. restore skb->mac_len There are two problems in 6-7 and 8-9. (a) After 6 & 7, skb->data points to the NSH header, so the outer header (ETH_P_8021AD in this case) is stripped when skb is sent out of netdev. Also, if NSH is encapsulated by NSH + Ethernet (so NSH-Ethernet-NSH), skb_pull() in the first nsh_gso_segment() will make skb->data point to the middle of the outer NSH or Ethernet header because the Ethernet header is not pulled by the second nsh_gso_segment(). (b) While restoring skb->{mac_header,network_header} in 8 & 9, nsh_gso_segment() does not assume that the data in the linear buffer is shifted. However, udp6_ufo_fragment() could shift the data and change skb->mac_header accordingly as demonstrated by syzbot. If this happens, even the restored skb->mac_header points to the middle of the outer header. It seems nsh_gso_segment() has never worked with outer headers so far. At the end of nsh_gso_segment(), the outer header must be restored for the segmented skb, instead of the NSH header. To do that, let's calculate the outer header position relatively from the inner header and set skb->{data,mac_header,protocol} properly. [0]: BUG: KMSAN: uninit-value in ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:524 [inline] BUG: KMSAN: uninit-value in ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline] BUG: KMSAN: uninit-value in ipvlan_queue_xmit+0xf44/0x16b0 drivers/net/ipvlan/ipvlan_core.c:668 ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:524 [inline] ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline] ipvlan_queue_xmit+0xf44/0x16b0 drivers/net/ipvlan/ipvlan_core.c:668 ipvlan_start_xmit+0x5c/0x1a0 drivers/net/ipvlan/ipvlan_main.c:222
__netdev_start_xmit include/linux/netdevice.h:4989 [inline] netdev_start_xmit include/linux/netdevice.h:5003 [inline] xmit_one net/core/dev.c:3547 [inline] dev_hard_start_xmit+0x244/0xa10 net/core/dev.c:3563 __dev_queue_xmit+0x33ed/0x51c0 net/core/dev.c:4351 dev_queue_xmit include/linux/netdevice.h:3171 [inline] packet_xmit+0x9c/0x6b0 net/packet/af_packet.c:276 packet_snd net/packet/af_packet.c:3081 [inline] packet_sendmsg+0x8aef/0x9f10 net/packet/af_packet.c:3113 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline]
__sys_sendto+0x735/0xa10 net/socket.c:2191 __do_sys_sendto net/socket.c:2203 [inline] __se_sys_sendto net/socket.c:2199 [inline] __x64_sys_sendto+0x125/0x1c0 net/socket.c:2199 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b Uninit was created at: slab_post_alloc_hook mm/slub.c:3819 [inline] slab_alloc_node mm/slub.c:3860 [inline] __do_kmalloc_node mm/slub.c:3980 [inline]
__kmalloc_node_track_caller+0x705/0x1000 mm/slub.c:4001 kmalloc_reserve+0x249/0x4a0 net/core/skbuff.c:582
__ ---truncated--- (CVE-2024-36933)
請注意，Nessus 依賴供應商報告的套件存在。
解決方案
目前尚未有已知的解決方案。Plugin 詳細資訊
嚴重性: Medium
ID: 228396
檔案名稱: unpatched_CVE_2024_36933.nasl
版本: 1.1
類型: local
代理程式: unix
系列: Misc.
已發布: 2025/3/5
已更新: 2025/3/5
支援的感應器: Nessus Agent, Nessus
風險資訊
VPR
風險因素: Medium
分數: 5.0
CVSS v2
風險因素: Medium
基本分數: 5.6
時間性分數: 4.1
媒介: CVSS2#AV:N/AC:H/Au:S/C:N/I:P/A:C
CVSS 評分資料來源: CVE-2024-36933
CVSS v3
風險因素: Medium
基本分數: 5.9
時間性分數: 5.2
媒介: CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:H
時間媒介: CVSS:3.0/E:U/RL:O/RC:C
弱點資訊
必要的 KB 項目: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched
可輕鬆利用: No known exploits are available
弱點發布日期: 2024/5/23
參考資訊
CVE: CVE-2024-36933